Consumer medicine information

CANDESARTAN HCTZ - GA

Candesartan cilexetil; Hydrochlorothiazide

BRAND INFORMATION

Brand name

Candesartan HCTZ-GA 16/12.5 Tablets

Active ingredient

Candesartan cilexetil; Hydrochlorothiazide

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using CANDESARTAN HCTZ - GA.

What is in this leaflet

This leaflet answers some common questions about CANDESARTAN HCTZ - GA.

It does not contain all of the available information. It does not take the place of talking to your doctor or pharmacist.

All medicines have benefits and risks. Your doctor has weighed the risks of you taking CANDESARTAN HCTZ - GA against the benefits they expect it will have for you.

If you have any concerns about taking this medicine, talk to your doctor or pharmacist.

Keep this leaflet with your medicine. You may need to read it again.

What CANDESARTAN HCTZ - GA is used for

CANDESARTAN HCTZ - GA is used to treat high blood pressure, also called hypertension.

CANDESARTAN HCTZ - GA contains two medicines, candesartan cilexetil and hydrochlorothiazide. In combination, they lower your blood pressure more than using either one on its own.

Candesartan cilexetil belongs to a group of medicines known as angiotensin-II receptor antagonists. It works by relaxing the blood vessels.

Hydrochlorothiazide is a diuretic. It works by reducing the amount of fluid in the body.

Your doctor will have explained why you are being treated with Candesartan/hydrochlorothiazide tablets and told you what dose to take.

Your doctor may have prescribed CANDESARTAN HCTZ - GA for another reason.

Ask your doctor if you have any questions about why CANDESARTAN HCTZ - GA has been prescribed for you.

CANDESARTAN HCTZ - GA is available only with a doctor's prescription.

Before you take CANDESARTAN HCTZ - GA

When you must not take it

Do not take CANDESARTAN HCTZ - GA if you are allergic to:

  • medicines containing candesartan cilexetil
  • other angiotensin II receptor antagonists
  • any sulphur drugs (sulphonamides) such as some antibiotics or some medicines to treat diabetes
  • any of the ingredients listed at the end of this leaflet.

Symptoms of an allergic reaction can include shortness of breath, wheezing or difficulty breathing, swelling of the face, lips, tongue, or other parts of the body.

Do not take CANDESARTAN HCTZ - GA if you have:

  • severe kidney or liver disease
  • gout.

Do not take CANDESARTAN HCTZ - GA if you are pregnant.

CANDESARTAN HCTZ - GA may affect your developing baby if you take it during pregnancy.

Do not breastfeed if you are taking CANDESARTAN HCTZ - GA.

It is not known if CANDESARTAN HCTZ - GA passes into breast milk.

Do not give CANDESARTAN HCTZ - GA to children.

There is no information about its use in children, so CANDESARTAN HCTZ - GA is not recommended for children.

Do not take CANDESARTAN HCTZ - GA if the expiry date (Exp.) printed on the pack has passed.

Do not take CANDESARTAN HCTZ - GA if the packaging is torn or shows signs of tampering.

Before you start to take it

Tell your doctor if you are allergic to any other medicines, foods, dyes or preservatives.

Tell your doctor if you have, or have had, any medical conditions, especially the following:

  • kidney problems
  • heart problems
  • liver problems
  • diabetes
  • recent excessive vomiting or diarrhoea
  • a salt reduced diet
  • Systemic Lupus Erythematosus (SLE), a disease affecting the skin, joints and kidneys
  • a condition called primary hyperaldosteronism
  • a past operation known as sympathectomy.

You may not be able to take CANDESARTAN HCTZ - GA or need a lower dose, if you have these conditions.

If you have not told your doctor about any of the above, tell them before you start taking CANDESARTAN HCTZ - GA.

Taking other medicines

Tell your doctor if you are taking any other medicines, including any that you buy without a prescription from a pharmacy, supermarket or health food shop.

Some medicines may be affected by CANDESARTAN HCTZ - GA, or may affect how well it works. These include:

  • other blood pressure lowering medicines
  • medicines containing potassium, including salt substitutes
  • digoxin, a medicine used to treat heart failure
  • non-steroidal anti-inflammatory drugs (NSAIDs), medicines used to relieve pain, swelling and other symptoms of inflammation, including arthritis
  • colestipol and cholestyramine, medicines used to treat high blood cholesterol levels
  • lithium, a medicine used to treat mood swings and some types of depression
  • alcohol
  • strong pain killers such as codeine, morphine, dextropropoxyphene
  • barbiturates, used to treat epilepsy, such as phenobarbitone
  • medicines like insulin that are used to treat diabetes
  • calcium supplements, or medicines containing calcium
  • medicines to treat irregular heart beats
  • corticosteroids such as prednisone, cortisone, dexamethasone.

Your doctor can tell you what to do if you are taking any of these medicines.

If you are not sure whether you are taking any of these medicines, check with your doctor or pharmacist.

Your doctor and pharmacist have more information on medicines to be careful with or avoid while taking CANDESARTAN HCTZ - GA.

Things to be careful of

Move slowly when getting out of bed or standing up if you feel faint, dizzy or light-headed.

Be careful driving or operating machinery until you know how CANDESARTAN HCTZ - GA affects you.

You may feel dizzy when you start taking CANDESARTAN HCTZ - GA due to the drop in your blood pressure.

Drink plenty of water while you are using CANDESARTAN HCTZ - GA, especially if you sweat a lot.

Please talk to your doctor or pharmacist about these possibilities if you think they may bother you.

How to take CANDESARTAN HCTZ - GA

How much to take

The usual dose is one tablet, taken once daily.

Take CANDESARTAN HCTZ - GA once a day, at about the same time each day.

Keeping a regular time for taking your medicine will help to remind you to take it.

Follow all directions given to you by your doctor and pharmacist carefully.

How to take CANDESARTAN HCTZ - GA

Swallow the tablets with a glass of water.

It does not matter whether you take CANDESARTAN HCTZ - GA tablets before or after food.

If you forget to take CANDESARTAN HCTZ - GA

If it is almost time for your next dose, skip the dose you missed and take your next dose when you are meant to.

Otherwise, take the missed dose as soon as you remember, and then go back to taking your tablets as you would normally.

Do not take a double dose to make up for the dose you missed.

If you are not sure what to do, ask your doctor or pharmacist.

How long to take CANDESARTAN HCTZ - GA for

CANDESARTAN HCTZ - GA helps control your high blood pressure but does not cure it. To properly control your condition, CANDESARTAN HCTZ - GA must be taken every day.

Keep taking CANDESARTAN HCTZ - GA for as long as your doctor recommends.

If you take too much CANDESARTAN HCTZ - GA (overdose)

Immediately telephone your doctor, or the Poisons Information Centre (telephone 13 11 26), or go to Accident and Emergency at the nearest hospital, if you think you or anyone else may have taken too much CANDESARTAN HCTZ - GA. Do this even if there are no signs of discomfort or poisoning.

You may need urgent medical attention.

If you take too much CANDESARTAN HCTZ - GA, you may get a headache and feel sick, dizzy, thirsty and very tired.

While you are taking CANDESARTAN HCTZ - GA

Things you must do

Before starting any new medicine, tell your doctor or pharmacist that you are taking CANDESARTAN HCTZ - GA.

Tell all the doctors, dentists and pharmacists who are treating you that you are taking CANDESARTAN HCTZ - GA.

Tell your doctor if you have excess vomiting and diarrhoea while taking CANDESARTAN HCTZ - GA.

You may lose too much water and your blood pressure may become too low.

Tell your doctor immediately if you become pregnant or plan to become pregnant while taking CANDESARTAN HCTZ - GA.

You should not use CANDESARTAN HCTZ - GA if you are pregnant or thinking about becoming pregnant. Your doctor can discuss different treatment options with you.

If you plan to have surgery, including dental surgery, that needs a general anaesthetic; tell your doctor or dentist that you are taking CANDESARTAN HCTZ - GA.

Tell your doctor if you plan to have an examination such as an X-ray or a scan requiring an injection of iodinated contrast (dye) that you are taking CANDESARTAN HCTZ - GA.

Be sure to keep all of your doctor's appointments so that your progress can be checked.

Your doctor will check your progress and may want to take some tests (eg blood tests, blood pressure) from time to time. These tests may help to prevent side effects.

Things you must not do

Do not use CANDESARTAN HCTZ - GA to treat any other conditions unless your doctor tells you to.

Do not give CANDESARTAN HCTZ - GA to anyone else, even if they have the same condition as you.

Do not stop taking CANDESARTAN HCTZ - GA unless you have discussed it with your doctor.

Things to be careful of

Be careful driving or operating machinery until you know how CANDESARTAN HCTZ - GA affects you.

CANDESARTAN HCTZ - GA may cause drowsiness, dizziness or lightheadedness in some people. If any of these occur, do not drive, operate machinery or do anything else that could be dangerous.

Be careful getting up from a sitting or lying position.

Dizziness, lightheadedness or fainting may occur, especially when you get up quickly. Getting up slowly may help. This problem can be more common if you are also taking a diuretic (fluid tablets). Standing up slowly, especially when you get up from bed or chairs, will help your body get used to the change in position and blood pressure.

If you are taking CANDESARTAN HCTZ - GA for high blood pressure, make sure you drink enough water during exercise and hot weather when you are taking CANDESARTAN HCTZ - GA, especially if you sweat a lot.

If you do not drink enough water while taking CANDESARTAN HCTZ - GA, you may faint or feel light-headed or sick. This is because your body does not have enough fluid and your blood pressure is low. If you continue to feel unwell, tell your doctor.

If you are taking CANDESARTAN HCTZ - GA for heart failure, restricted fluid intake is generally recommended. Speak with your doctor about how much water you should drink.

Please talk to your doctor or pharmacist about these possibilities if you think they may bother you.

Side effects

Tell your doctor or pharmacist as soon as possible if you do not feel well while you are taking CANDESARTAN HCTZ - GA.

Like all other medicines, CANDESARTAN HCTZ - GA may have unwanted side effects in some people. Sometimes they are serious, most of the time they are not. You may need medical treatment if you get some of the side effects.

Do not be alarmed by this list of possible side effects.

You may not experience any of them.

Ask your doctor or pharmacist to answer any questions you may have.

Tell your doctor if you notice any of the following and they worry you:

  • headache or dizziness
  • chest, throat or sinus infection
  • flu-like symptoms or infections
  • feeling sick (nausea) or vomiting
  • back pain
  • urinary tract infection
  • feeling tired
  • stomach ache.

These are common side effects.

They are generally mild and do not normally require treatment to be interrupted.

The following side effects have been reported very rarely by patients taking CANDESARTAN HCTZ - GA: palpitations, agitation, anxiety, depression, trouble sleeping (insomnia), drowsiness (somnolence), nervousness, nightmare and sleep disorder. It is not known if these side effects are caused by CANDESARTAN HCTZ - GA.

Tell your doctor immediately if you notice any of the following:

  • rapid heartbeats
  • aching muscles, tenderness or weakness in the muscles.

This list includes serious side effects that may require medical attention. Serious side effects are rare.

If any of the following happen, tell your doctor immediately or go to Accident and Emergency at your nearest hospital:

  • swelling of the face, lips, tongue or throat which may cause difficulty in swallowing or breathing
  • swelling of hands, feet or ankles
  • harsh sounds when breathing
  • rash, itching or hives
  • signs of frequent infections such as fever, severe chills, sore throat or mouth ulcers
  • jaundice (yellowing of the skin and /or eyes)
  • easy bruising or bleeding more easily than normal
  • extreme fatigue, tiredness, weakness
  • worsening of kidney function (including passing little or no urine, drowsiness, nausea, vomiting, breathlessness, loss of appetite and weakness (especially in patients with existing kidney problems or heart failure)
  • changes in your potassium, sodium and red or white blood cell levels may occur. Such changes are usually detected by a blood test.
  • symptoms that may indicate high potassium levels in the blood include nausea, diarrhoea, muscle weakness and changes in heart rhythm.

These are very rare but serious side effects. If you have them, you may have had a serious reaction to the medicine. You may need urgent medical attention or hospitalisation.

Other side effects not listed above may also occur in some patients. Tell your doctor if you notice anything that is making you feel unwell.

After using CANDESARTAN HCTZ - GA

Storage

Keep CANDESARTAN HCTZ - GA where children cannot reach it.

A locked cupboard at least one-and-a-half metres above the ground is a good place to store medicines.

Keep your tablets in a cool dry place where the temperature stays below 25°C.

Do not store CANDESARTAN HCTZ - GA or any other medicine in the bathroom or near a sink.

Do not leave CANDESARTAN HCTZ - GA in the car or on window sills.

Heat and dampness can destroy some medicines.

Disposal

If your doctor tells you to stop taking CANDESARTAN HCTZ - GA, or your tablets have passed their expiry date, ask your pharmacist what to do with any that are left over.

Product description

What it looks like

CANDESARTAN HCTZ - GA comes in 3 strengths of tablets:

  • CANDESARTAN HCTZ - GA 16/12.5 - light pink, oval, biconvex tablet with ‘L3|02’ on one side and a break line on the other side
  • CANDESARTAN HCTZ - GA 32/12.5 - light yellow, oval, biconvex tablet with ‘L3|04’ on one side and a break line on the other side
  • CANDESARTAN HCTZ - GA 32/25 - light pink, oval, biconvex tablet with ‘L3|04’ on one side and a break line on the other side

Each Aluminium/Aluminium foil blister pack contains 30 tablets.

Ingredients

The active ingredients in CANDESARTAN HCTZ - GA are candesartan cilexetil and hydrochlorothiazide.

  • each CANDESARTAN HCTZ - GA 16/12.5 tablet contains 16 mg of candesartan cilexetil and 12.5 mg of hydrochlorothiazide
  • each CANDESARTAN HCTZ - GA 32/12.5 tablet contains 32 mg of candesartan cilexetil and 12.5 mg of hydrochlorothiazide
  • each CANDESARTAN HCTZ - GA 32/25 tablet contains 32 mg of candesartan cilexetil and 25 mg of hydrochlorothiazide.

The tablets also contain:

  • lactose
  • carmellose calcium
  • maize starch
  • macrogol 8000
  • hydroxypropylcellulose
  • magnesium stearate
  • Pigment Blend PB-24880 Pink (16/12.5 mg and 32/25 tablet only)
  • yellow colouring (iron oxide yellow and lactose) (32/12.5 mg tablet only).

The tablets do not contain gluten, sucrose, tartrazine or any other azo dyes.

Sponsor

Actavis Pty Ltd
Level 5, 117 Harrington St
The Rocks NSW 2000

Australian registration numbers:
CANDESARTAN HCTZ - GA 16/12.5 - AUST R 204583
CANDESARTAN HCTZ - GA 32/12.5 - AUST R 204584
CANDESARTAN HCTZ - GA 32/25 - AUST R 204585

Date of preparation: June 2013
Updated: April 2014

BRAND INFORMATION

Brand name

Candesartan HCTZ-GA 16/12.5 Tablets

Active ingredient

Candesartan cilexetil; Hydrochlorothiazide

Schedule

S4

 

Name of the medicine

Candesartan HCTZ-GA 16/12.5.

Candesartan cilexetil 16 mg, hydrochlorothiazide 12.5 mg.

Candesartan HCTZ-GA 32/12.5.

Candesartan cilexetil 32 mg, hydrochlorothiazide 12.5 mg.

Candesartan HCTZ-GA 32/25.

Candesartan cilexetil 32 mg, hydrochlorothiazide 25 mg.

Excipients.

Lactose, carmellose calcium, maize starch, macrogol 8000, hydroxypropylcellulose, magnesium stearate, Pigment Blend PB-24880 Pink (ARTG 108327; 16/12.5 mg and 32/25 mg tablets only) and yellow colouring (iron oxide yellow and lactose) in the 32/12.5 mg tablets only. The tablets are gluten free.

Description

Candesartan cilexetil.

Chemical name: (1RS)-1-[[(cyclohexyloxy)carbonyl]-oxy) ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl) biphenyl-4-yl] methyl]-1H-benzimadozole-7-carboxylate. Molecular formula: C33H34N6O6. MW: 611. CAS: 145040-37-5. Candesartan cilexetil is a white or almost white powder and is practically insoluble in water, freely soluble in methylene chloride and slightly soluble in anhydrous ethanol. Three polymorphic forms have been identified; crystal form I, crystal form II and an amorphous form. Crystalline form I is used in Candesartan HCTZ-GA.

Hydrochlorothiazide.

Chemical name: 6-chloro-3,4-dihydro- 2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide. Molecular formula: C7H8ClN3O4S2. MW: 297.7. CAS: 58-93-5. Hydrochlorothiazide is a white, crystalline powder. It is very slightly soluble in water, soluble in acetone, sparingly soluble in ethanol (96 per cent). It dissolves in dilute solutions of alkali hydroxides.

Pharmacology

Angiotensin II is the primary vasoactive hormone of the renin angiotensin aldosterone system and plays a significant role in the pathophysiology of hypertension and other cardiovascular disorders. It also has an important role in the pathogenesis of end organ hypertrophy and damage. The major physiological effects of angiotensin II, such as vasoconstriction, aldosterone stimulation, regulation of salt and water homeostasis and stimulation of cell growth, are mediated via the type 1 (AT1) receptor.
Candesartan cilexetil is a prodrug suitable for oral use. It is rapidly converted to the active drug, candesartan, by ester hydrolysis during absorption from the gastrointestinal tract. Candesartan is an angiotensin II receptor antagonist, selective for AT1 receptors, with tight binding to and slow dissociation from the receptor. It has no agonist activity.
Candesartan does not inhibit angiotensin converting enzyme (ACE), which converts angiotensin I to angiotensin II and degrades bradykinin. Since there is no effect on ACE and no potentiation of bradykinin or substance P, angiotensin II receptor antagonists are unlikely to be associated with cough. This has been confirmed in controlled clinical studies with candesartan. Candesartan does not bind to or block other hormone receptors or ion channels known to be important in cardiovascular regulation.
Hydrochlorothiazide inhibits the active reabsorption of sodium, mainly in the distal kidney tubules, and promotes the excretion of sodium, chloride and water. The renal excretion of potassium and magnesium increases dose dependently, while calcium is reabsorbed to a greater extent. Hydrochlorothiazide decreases plasma volume and extracellular fluid and reduces cardiac output and blood pressure. During long-term therapy, reduced peripheral resistance contributes to the blood pressure reduction.
Candesartan and hydrochlorothiazide have additive antihypertensive effects. In hypertensive patients, it results in dose dependent and long lasting reduction in arterial blood pressure without a reflex increase in heart rate. There is no indication of serious or exaggerated first dose hypotension or rebound effect after cessation of treatment.
After administration of a single dose of candesartan with hydrochlorothiazide, onset of the antihypertensive effect generally occurs within 2 hours. With continuous treatment, most of the reduction in blood pressure is attained within four weeks and is sustained during long-term treatment.
Candesartan with hydrochlorothiazide once daily provides effective and smooth blood pressure reduction over 24 hours, with little difference between maximum and trough effects during the dosing interval. In double blind, randomised studies, the incidence of cough was lower during treatment with candesartan cilexetil/ hydrochlorothiazide than during treatment with combinations of ACE inhibitors and hydrochlorothiazide.
Age and gender have no influence on the efficacy of candesartan with hydrochlorothiazide tablets.
In a variety of preclinical safety studies conducted in several species, expected exaggerated pharmacological effects (e.g. renal changes leading to juxtaglomerular cell hypertrophy, adrenal gland zona glomerulosa atrophy and reduced heart weight related to reduced afterload), due to modification of the renin angiotensin aldosterone system homeostasis, have been observed. The incidence and severity of the effects induced were dose and time related and have been shown to be reversible in adult animals. Addition of hydrochlorothiazide caused a potentiation of the nephrotoxicity seen with candesartan alone, however, without any qualitatively new findings.

Pharmacokinetics.

The individual pharmacokinetic profiles of candesartan and hydrochlorothiazide were not clinically significantly affected when given in combination.

Absorption and distribution.

Candesartan cilexetil.

Following oral administration, candesartan cilexetil is converted to the active drug candesartan. The absolute bioavailability of candesartan is approximately 40% after an oral solution of candesartan cilexetil. The relative bioavailability of the tablet formulation compared with the same oral solution is approximately 34%, with little variability. The absolute bioavailability of candesartan following administration of the tablet is approximately 14%. The mean peak plasma concentration (Cmax) is reached 3-4 hours after taking a tablet. The candesartan plasma concentrations increase linearly with increasing doses in the therapeutic dose range.
The area under the plasma concentration versus time curve (AUC) of candesartan is not significantly affected by food. The peak concentration (Cmax) is increased by 26% and the rate of absorption is increased when taken with food. These changes are unlikely to result in clinically significant effects.
Candesartan is highly bound to plasma protein (more than 99%). The apparent volume of distribution (Vss) of candesartan is 0.1 L/kg.

Hydrochlorothiazide.

Hydrochlorothiazide is rapidly absorbed from the gastrointestinal tract with an absolute bioavailability of approximately 70%. Concomitant intake of food increases the absorption by approximately 15%. The bioavailability may decrease in patients with cardiac failure and pronounced oedema.
The plasma protein binding of hydrochlorothiazide is approximately 60%. The apparent volume of distribution is approximately 0.8 L/kg.

Metabolism and elimination.

Candesartan cilexetil.

Candesartan cilexetil is mainly eliminated unchanged via urine and bile and is eliminated by hepatic metabolism only to a minor extent (CYP2C9). The terminal half-life of candesartan is approximately 9 hours. There is no accumulation following multiple doses.
The half-life of candesartan remains unchanged (approximately 9 h) after administration of candesartan cilexetil in combination with hydrochlorothiazide. No accumulation of candesartan occurs after repeated doses of the combination compared to monotherapy.
Total plasma clearance of candesartan is about 0.37 mL/min/kg, with a renal clearance of about 0.19 mL/min/kg. The renal elimination of candesartan is both by glomerular filtration and active tubular secretion. Following an oral dose of 14C-labelled candesartan cilexetil about 30% and 70% of the total radioactivity is recovered in the urine and faeces, respectively.

Hydrochlorothiazide.

Hydrochlorothiazide is not metabolised and is excreted almost entirely as unchanged drug by glomerular filtration and active tubular secretion. The terminal t1/2 of hydrochlorothiazide is approximately 8 hours. Approximately 70% of an oral dose is eliminated in the urine within 48 hours. The half-life of hydrochlorothiazide remains unchanged (approximately 8 h) after administration of hydrochlorothiazide in combination with candesartan cilexetil. No accumulation of hydrochlorothiazide occurs after repeated doses of the combination compared to monotherapy.

Pharmacokinetics in special populations.

Candesartan cilexetil.

In the elderly (over 65 years) both Cmax and AUC of candesartan are increased by approximately 50% and 80% respectively, in comparison to young subjects.
However, the blood pressure response and the incidence of adverse events are similar after a given dose of candesartan with hydrochlorothiazide in young and elderly patients.
In patients with mild to moderate renal impairment, Cmax and AUC of candesartan increased during repeated dosing by approximately 50% and 70% respectively, but t1/2 was not altered compared to patients with normal renal function. The corresponding changes in patients with severe renal impairment were approximately 50% and 110% respectively. The terminal t1/2 of candesartan was approximately doubled in patients with severe renal impairment. The pharmacokinetics in patients undergoing haemodialysis were similar to those in patients with severe renal impairment.
In patients with mild to moderate hepatic impairment, there was a 23% increase in the AUC of candesartan. No initial dosage adjustment is necessary in these patients.

Hydrochlorothiazide.

The terminal t1/2 of hydrochlorothiazide is prolonged in patients with renal impairment.

Clinical Trials

In a randomised, double blind, parallel group, 8 week clinical study, including 1975 randomised patients not adequately controlled on 32 mg candesartan cilexetil once daily, the addition of 12.5 mg or 25 mg hydrochlorothiazide resulted in additional blood pressure reductions of 7/3 mmHg and 9/4 mmHg respectively over 32 mg monotherapy. The candesartan cilexetil/ hydrochlorothiazide 32/12.5 mg and 32/25 mg combinations produced overall mean blood pressure reductions of 13/9 mmHg and 16/10 mmHg, respectively. This study also demonstrated that the 32/25 mg combination was significantly more effective than the 32/12.5 mg combination.
In two 8 week clinical studies (randomised, double blind, placebo controlled, parallel group) including 275 and 1524 randomised patients respectively, the candesartan cilexetil/ hydrochlorothiazide combinations 32/12.5 mg and 32/25 mg resulted in blood pressure reductions of 21/14 mmHg for the highest dose, and were significantly more effective than the respective monotherapy components.
Epidemiological studies have shown that long-term treatment with hydrochlorothiazide reduces the risk for cardiovascular morbidity and mortality. There are no data regarding the effects of candesartan cilexetil and candesartan cilexetil/ hydrochlorothiazide on morbidity and mortality in hypertensive patients.

Indications

Treatment of hypertension. Treatment should not be initiated with this fixed dose combination.

Contraindications

Hypersensitivity to any component of Candesartan HCTZ-GA tablets or to sulfonamide derived drugs.
Pregnancy (see Precautions, Use in pregnancy).
Severe renal impairment (creatinine clearance < 30 mL/min/1.73 m2 BSA).
Severe hepatic impairment and/or cholestasis.
Gout.

Precautions

General.

In patients whose vascular tone and renal function depend predominantly on the activity of the renin angiotensin aldosterone system (e.g. patients with severe congestive heart failure or underlying renal disease, including renal artery stenosis), treatment with drugs that affect this system has been associated with acute hypotension, azotaemia, oliguria or, rarely, acute renal failure. As with any antihypertensive agent, excessive blood pressure decrease in patients with ischaemic heart disease or atherosclerotic cerebrovascular disease could result in a myocardial infarction or stroke.

Renal artery stenosis.

Other drugs that affect the renin angiotensin aldosterone system, i.e. angiotensin converting enzyme (ACE) inhibitors, may increase blood urea and serum creatinine in patients with bilateral renal artery stenosis or stenosis of the artery to a solitary kidney. A similar effect may be anticipated with angiotensin II receptor antagonists.

Aortic and mitral valve stenosis or obstructive hypertrophic cardiomyopathy.

As with other vasodilators, special caution is indicated in patients suffering from haemodynamically relevant aortic or mitral valve stenosis, or obstructive hypertrophic cardiomyopathy.

Primary hyperaldosteronism.

Patients with primary hyperaldosteronism will not generally respond to antihypertensive drugs acting through inhibition of the renin angiotensin aldosterone system. Therefore, the use of candesartan in these patients is not recommended.

Fluid and electrolyte imbalance.

As for any patient receiving diuretic therapy, periodic determination of serum electrolytes should be performed at appropriate intervals.
Thiazides, including hydrochlorothiazide, can cause fluid or electrolyte imbalance (hypercalcaemia, hypokalaemia, hyponatraemia, hypomagnesaemia and hypochloraemic alkalosis).
Hydrochlorothiazide dose dependently increases urinary potassium excretion which may result in hypokalaemia. This effect of hydrochlorothiazide seems to be less evident when combined with candesartan cilexetil. The risk of hypokalaemia may be increased in patients with cirrhosis of the liver, in patients experiencing brisk diuresis, in patients with an inadequate oral intake of electrolytes and in patients receiving concomitant therapy with corticosteroids or adrenocorticotropic hormone (ACTH).
Based on experience with the use of other drugs that affect the renin angiotensin aldosterone system, concomitant use of candesartan with hydrochlorothiazide tablets and potassium sparing diuretics, potassium supplements or salt substitutes or other drugs that may increase serum potassium levels may lead to increases in serum potassium.

Renal impairment.

When Candesartan HCTZ-GA is used in patients with renal impairment, periodic monitoring of serum potassium, creatinine and uric acid levels is recommended. Loop diuretics are preferred to thiazides in this population.
There is no experience regarding the administration of candesartan with hydrochlorothiazide tablets in patients with a recent kidney transplantation.

Combination use of ACE inhibitors or angiotensin receptor antagonists, anti-inflammatory drugs and thiazide diuretics.

The use of an ACE inhibiting drug (ACE inhibitor or angiotensin receptor antagonist), an anti-inflammatory drug (NSAID or COX-2 inhibitor) and a thiazide diuretic at the same time increases the risk of renal impairment. This includes use in fixed combination products containing more than one class of drug. Combined use of these medications should be accompanied by increased monitoring of serum creatinine, particularly at the institution of the combination. The combination of drugs from these three classes should be used with caution particularly in elderly patients or those with pre-existing renal impairment.

Hepatic impairment.

Thiazides should be used with caution in patients with impaired hepatic function or progressive liver disease, since minor alterations of fluid and electrolyte balance may precipitate hepatic coma. There is no clinical experience with candesartan with hydrochlorothiazide tablets in patients with hepatic impairment.

Metabolic and endocrine effects.

Treatment with a thiazide diuretic may impair glucose tolerance. Dosage adjustment of antidiabetic drugs, including insulin, may be required. Latent diabetes mellitus may become manifest during thiazide therapy. Increases in cholesterol and triglyceride levels have been associated with thiazide diuretic therapy. At the doses contained in Candesartan HCTZ-GA, only minimal effects were observed. Thiazide diuretics increase serum uric acid concentration and may precipitate gout in susceptible patients.

Hypotension, volume depleted patients.

Candesartan HCTZ-GA, like all antihypertensive agents may cause symptomatic hypotension in some patients. Symptomatic hypotension may be expected to occur more frequently in patients who have been sodium and/or volume depleted by vigorous diuretic therapy and/or dietary salt restrictions, or vomiting and/or diarrhoea or haemodialysis. Sodium and/or volume depletion should be corrected prior to administration of Candesartan HCTZ-GA.

Postsympathectomy.

The antihypertensive effects of thiazide diuretics may be increased in the postsympathectomy patient.

Systemic lupus erythematosus.

Exacerbation or activation of systemic lupus erythematosus has been reported with the use of thiazide diuretics.

Anaesthesia and surgery.

Hypotension may occur during anaesthesia and surgery in patients treated with angiotensin II antagonists due to blockade of the renin angiotensin aldosterone system. Very rarely, hypotension may be severe such that it may warrant the use of intravenous fluids and/or vasopressors.

Paediatric use.

Safety and efficacy have not been established in children.

Use in the elderly.

For dosage recommendations for use of Candesartan HCTZ-GA in elderly patients, see Dosage and Administration.

Effects on fertility.

The effects of hydrochlorothiazide alone or in combination with candesartan cilexetil on fertility have not been evaluated in animal studies. However, candesartan cilexetil alone had no adverse effects on the reproductive performance of male or female rats at oral doses up to 300 mg/kg/day.

Use in pregnancy.

(Category D)
The use of Candesartan HCTZ-GA is contraindicated during pregnancy (see Contraindications). Patients receiving Candesartan HCTZ-GA should be made aware of that before contemplating a possibility of becoming pregnant so that they can discuss appropriate options with their treating physician. When pregnancy is diagnosed, treatment with Candesartan HCTZ-GA must be stopped immediately and if appropriate, alternative therapy should be started.
The use of drugs that act directly on the renin angiotensin system has been associated with foetal and neonatal injury, including hypotension, neonatal skull hypoplasia, anuria, reversible or irreversible renal failure, and death. Exposure to angiotensin II receptor antagonist therapy is known to induce human foetotoxicity (decreased renal function, oligohydramnios, skull ossification retardation) and neonatal toxicity (renal failure, hypotension, hyperkalaemia).
There is limited experience with hydrochlorothiazide during pregnancy, especially during the first trimester. Animal studies are insufficient. Hydrochlorothiazide crosses the placenta. Based on the pharmacological mechanism of action of hydrochlorothiazide, its use during pregnancy may compromise foetoplacental perfusion and may cause foetal and neonatal effects like icterus, disturbance of electrolyte balance and thrombocytopenia.

Use in lactation.

It is not known whether candesartan is excreted in human milk. However, candesartan is excreted in the milk of lactating rats. Hydrochlorothiazide passes into human milk. Because of the potential for adverse effects on the nursing infant, breastfeeding should be discontinued if the use of Candesartan HCTZ-GA is considered essential.

Carcinogenicity.

The carcinogenic potential of candesartan cilexetil in combination with hydrochlorothiazide has not been evaluated in animal studies.
Candesartan cilexetil alone was not carcinogenic when administered orally to mice and rats for 2 years at doses of up to 100 and 1000 mg/kg/day, corresponding to ca. 7 times and 260 times the clinical exposure at the maximum recommended daily human dose of 32 mg (based on AUC, respectively).
Hydrochlorothiazide alone was not carcinogenic in female mice in doses ca. 600 mg/kg/day, or in male and female rats at doses up to ca. 100 mg/kg/day in two year feeding studies. These doses correspond to ca. 110 times (female mice) or 40 times (male and female rats) the clinical exposure at the maximum recommended daily human dose of 25 mg (based on BSA). However, there was equivocal evidence for hepatocarcinogenicity in male mice that received ca. 600 mg/kg/day.

Genotoxicity.

Candesartan cilexetil alone or in combination with hydrochlorothiazide showed no evidence of genotoxic potential in a series of assays for gene mutations (Salmonella typhimurium and Escherichia coli), chromosomal aberrations (mouse micronucleus assay) and DNA damage (unscheduled DNA synthesis in rat liver). In addition, candesartan cilexetil alone showed no evidence of genotoxic potential in further assays for gene mutations (mouse L5178Y cells and Chinese hamster ovary cells). The active metabolite, candesartan, caused an increase in chromosomal aberrations in vitro (Chinese hamster lung cells) but not in vivo (mouse micronucleus test and chromosomal aberrations in rat bone marrow). However, hydrochlorothiazide had mutagenic activity in a mammalian cell assay (mouse L5178Y cells) and caused an increase in chromosomal aberrations in vitro (Chinese hamster lung cells). Candesartan at subclastogenic concentration did not modify these effects of hydrochlorothiazide. Hydrochlorothiazide also had a genotoxic activity in the sister chromatid exchange assay in Chinese hamster ovary cells and a nondisjunction assay in Aspergillus nidulans.

Effects on ability to drive and use machines.

When driving vehicles or operating machines, it should be taken into account that dizziness or weariness may occur during treatment of hypertension.

Interactions

The antihypertensive effect of Candesartan HCTZ-GA may be enhanced by other antihypertensives.

Candesartan cilexetil.

Compounds which have been investigated include hydrochlorothiazide, warfarin, digoxin (see Hydrochlorothiazide below), oral contraceptives (i.e. ethinyloestradiol/ levonorgestrel), glibenclamide and nifedipine. No pharmacokinetic interactions of clinical significance were identified in these studies.
Attenuation of the antihypertensive effect may occur when simultaneously administering AIIRAs and nonsteroidal anti-inflammatory drugs (NSAIDs; i.e. selective COX-2 inhibitors, acetylsalicylic acid (> 3 g/day) and nonselective NSAIDs).
As with ACE inhibitors, concomitant use of AIIRAs and NSAIDs may lead to an increased risk of worsening of renal function, including possible acute renal failure, and an increase in serum potassium, especially in patients with poor pre-existing renal function. The combination should be administered with caution, especially in older patients and in volume depleted patients. Patients should be adequately hydrated and consideration should be given to monitoring renal function after initiation of concomitant therapy and periodically thereafter.
Candesartan is eliminated only to a minor extent by hepatic metabolism (CYP2C9).
Interaction studies performed to date show no effect of candesartan on the metabolising capacity of CYP2C9 and CYP3A4. Based on in vitro data, no interaction would be expected to occur in vivo with drugs whose metabolism is dependent upon cytochrome P450 isoenzymes CYP1A2, CYP2A6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 or CYP3A4.

Hydrochlorothiazide.

Alcohol, barbiturates or opioids.

Potentiation of thiazide diuretic induced orthostatic hypotension may occur.

Antidiabetic agents (oral and insulin).

Thiazides may increase blood glucose concentration and adjustment of antidiabetic medication may be required.

Cardiac glycosides and other antiarrhythmics.

Thiazide induced hypokalaemia and hypomagnesaemia predisposes to the potential cardiotoxic effects of digitalis glycosides and antiarrhythmics. Periodic monitoring of serum potassium is recommended when Candesartan HCTZ-GA is administered with such drugs.

Calcium salts.

Thiazide diuretics may increase the serum calcium concentration due to decreased excretion. If calcium is prescribed, serum calcium levels should be monitored and calcium dosage adjusted accordingly.

Cholestyramine resin and colestipol hydrochloride.

The absorption of thiazide may be delayed or decreased in the presence of bile acids sequestrants. Candesartan HCTZ-GA should be taken at least one hour before or after such drugs.

Lithium.

Reversible increases in serum lithium concentrations and toxicity have been reported during concomitant administration of lithium with ACE inhibitors or hydrochlorothiazide. A similar effect may occur with angiotensin II receptor antagonists (AIIRAs) and careful monitoring of serum lithium levels is recommended during concomitant use.

Nonsteroidal anti-inflammatory drugs (NSAIDs).

The diuretic, natriuretic and antihypertensive effect of hydrochlorothiazide is blunted by NSAIDs.

Hypokalaemic agents.

The potassium depleting effect of hydrochlorothiazide could be expected to be potentiated by other drugs associated with potassium loss and hypokalaemia (e.g. other kaliuretic diuretics, laxatives, amphotericin, carbenoxolone, salicylic acid derivatives).

Potassium sparing agents.

Based on experience with the use of other drugs that affect the renin angiotensin aldosterone system, concomitant use of Candesartan HCTZ-GA and potassium sparing diuretics, potassium supplements or salt substitutes or other drugs that may increase serum potassium levels (e.g. heparin sodium) may lead to increases in serum potassium.

Nondepolarizing muscle relaxants (e.g. tubocurarine).

The effect of nondepolarising skeletal muscle relaxants (e.g. tubocurarine) may be potentiated by hydrochlorothiazide.

Pressor amines.

Hydrochlorothiazide may cause the arterial response to pressor amines to decrease but not enough to exclude a pressor effect.

Iodinated contrast media.

Hydrochlorothiazide may increase the risk of acute renal insufficiency especially with high doses of iodinated contrast media.

Corticosteroids, ACTH.

The risk for hypokalaemia may be increased during concomitant use of steroids or adrenocorticotropic hormone (ACTH).

Amantadine.

Thiazides may increase the risk of adverse effects caused by amantadine.

Beta-blockers and diazoxide.

The hyperglycaemic effect of beta-blockers and diazoxide may be enhanced by thiazides.

Anticholinergic agents (e.g. atropine).

Anticholinergic agents (e.g. atropine, biperiden) may increase the bioavailability of thiazide diuretics by decreasing gastrointestinal motility and stomach emptying rate.

Cytotoxic drugs (e.g. cyclophosphamide, methotrexate).

Thiazides may reduce the renal excretion of cytotoxic drugs (e.g. cyclophosphamide, methotrexate) and potentiate their myelosuppressive effects.

Adverse Effects

Adverse events were mild and transient in controlled clinical studies with various doses of candesartan cilexetil/ hydrochlorothiazide (candesartan cilexetil up to 32 mg and hydrochlorothiazide up to 25 mg). The overall incidence of adverse events showed no association with age or gender. Withdrawals from treatment due to adverse events were similar with candesartan cilexetil/ hydrochlorothiazide (2.3-3.3%) and placebo (2.7-4.3%).
Clinical adverse events, regardless of causal relationship, with a cumulative 8 week incidence rate of ≥ 1% during treatment with candesartan cilexetil/ hydrochlorothiazide up to 16/12.5 mg in double blind, placebo controlled trials are presented in Table 1.
The following clinical adverse events occurred with a frequency of 0.5% to < 1% with no occurrence in the placebo group: AV block, vomiting.
Clinical adverse events, regardless of causal relationship, occurring in ≥ 1% of the patients during 8 week randomised treatment with candesartan cilexetil/ hydrochlorothiazide 32/12.5 mg and 32/25 mg in double blind clinical trials are presented in Table 2.

Adverse events on individual components.

Candesartan cilexetil.

The following clinical adverse events, regardless of whether attributed to therapy, have been reported to occur with a cumulative 8 week incidence rate of ≥ 1% in placebo controlled clinical trials with candesartan cilexetil monotherapy: cough, diarrhoea, peripheral oedema and rhinitis. Angioedema, urticaria, pruritus and rash have been reported very rarely in patients treated with candesartan cilexetil. Very rare cases of increased liver enzymes, abnormal hepatic function or hepatitis have also been reported. Very rare adverse reactions include hyponatraemia, hyperkalaemia and renal impairment, including renal failure in susceptible patients (see Precautions). Other adverse events reported for candesartan cilexetil where a causal relationship could not be established include very rare cases of leukopenia, neutropenia and agranulocytosis.

Hydrochlorothiazide.

The following clinical adverse events have been reported to occur with hydrochlorothiazide monotherapy: anorexia, loss of appetite, gastric irritation, diarrhoea, constipation, jaundice (intrahepatic cholestatic jaundice), pancreatitis, leucopenia, neutropenia/ agranulocytosis, thrombocytopenia, aplastic anaemia, haemolytic anaemia, bone marrow depression, photosensitivity reactions, fever, rash, cutaneous lupus erythematosus-like reactions, reactivation of cutaneous lupus erythematosus, urticaria, necrotising angiitis (vasculitis, cutaneous vasculitis), anaphylactic reactions, toxic epidermal necrolysis, respiratory distress (including pneumonitis and pulmonary oedema), hyperglycaemia, glycosuria, hyperuricaemia, electrolyte imbalance (including hyponatraemia and hypokalaemia), increases in cholesterol and triglycerides, increases in BUN and serum creatinine, renal dysfunction, interstitial nephritis, muscle spasm, weakness, restlessness, transient blurred vision, lightheadedness, postural hypotension, vertigo, paraesthesia, cardiac arrhythmias, sleep disturbances, depression, acute myopia, acute angle closure glaucoma.

Laboratory findings.

In general, there were no clinically important influences of candesartan cilexetil/ hydrochlorothiazide on routine laboratory variables. Increases in creatinine, urea, potassium, uric acid, glucose and ALAT (SGPT), and decreases in sodium have been observed. Minor decreases in haemoglobin and increases in ASAT (SGOT) have been observed in single patients.

Postmarketing.

The following adverse reactions have been reported very rarely (< 0.01%) in postmarketing experience.

Musculoskeletal, connective tissue and bone disorders.

Myalgia.
Rare reports of rhabdomyolysis have been reported in patients receiving angiotensin II receptor blockers.
Although causality to candesartan has not been established, the following neuropsychiatric and cardiovascular adverse reactions have been very rarely reported during postmarketing surveillance. These were agitation, anxiety, depression, insomnia, somnolence, nervousness, nightmare, sleep disorder and palpitations.

Dosage and Administration

The dose of candesartan with hydrochlorothiazide combination tablets must be determined by careful titration of the dose of each of the individual components.
The recommended dose is 1 tablet once daily. The tablets may be taken with or without food. The tablets should not be divided.
Candesartan HCTZ-GA 16/12.5 may be administered in patients whose blood pressure is not optimally controlled with hydrochlorothiazide alone or candesartan cilexetil 16 mg monotherapy.
Candesartan HCTZ-GA 32/12.5 or 32/25 may be administered in patients whose blood pressure is not optimally controlled with hydrochlorothiazide alone or candesartan 32 mg monotherapy, or at a lower dose of Candesartan HCTZ-GA. Dose titration of candesartan cilexetil is recommended when adding on to hydrochlorothiazide monotherapy.
Most of the antihypertensive effect is usually attained within 4 weeks of initiation of treatment.
Candesartan HCTZ-GA should not be used to initiate treatment.

Paediatrics.

The safety and efficacy of candesartan cilexetil with hydrochlorothiazide tablets has not been established in children.

Geriatrics.

Dose titration of candesartan cilexetil is recommended before treatment with candesartan cilexetil with hydrochlorothiazide tablets.

Hepatic impairment.

Dose titration of candesartan cilexetil is recommended before treatment with candesartan cilexetil with hydrochlorothiazide tablets in patients with mild to moderate hepatic impairment.
Candesartan HCTZ-GA should not be used in patients with severe hepatic impairment and/or cholestasis.

Renal impairment.

Loop diuretics are preferred to thiazides in this population. Dose titration of candesartan cilexetil is recommended before treatment with Candesartan HCTZ-GA in patients with renal impairment whose creatinine clearance is ≥ 30 mL/min/1.73 m2 BSA.
Candesartan HCTZ-GA should not be used in patients with severe renal impairment (creatinine clearance < 30 mL/min/1.73 m2 BSA).

Intravascular volume depletion.

Patients who are severely volume and/or sodium depleted should have this corrected before being treated with Candesartan HCTZ-GA.

Overdosage

Symptoms.

Based on pharmacological considerations, the main manifestation of an overdose of candesartan cilexetil is likely to be symptomatic hypotension and dizziness. In two case reports of overdose (160 mg and 432 mg candesartan cilexetil) patient recovery was uneventful.
The main manifestation of an overdose of hydrochlorothiazide is acute loss of fluid and electrolytes. Symptoms such as dizziness, hypotension, thirst, tachycardia, ventricular arrhythmias, sedation/ impairment of consciousness and muscle cramps can also be observed.

Management.

No specific information is available on the treatment of overdosage with candesartan cilexetil with hydrochlorothiazide tablets. The following measures are, however, suggested in case of overdosage.
Administration of activated charcoal with or without gastric lavage. If symptomatic hypotension should occur, symptomatic treatment should be instituted and vital signs monitored. The patient should be placed supine with the legs elevated. If this is not sufficient, plasma volume should be increased by infusion of isotonic saline solution. Serum electrolyte and acid balance should be checked and corrected, if needed. Sympathomimetic drugs may be administered if the abovementioned measures are not sufficient.
Candesartan cannot be removed by haemodialysis. It is not known to what extent hydrochlorothiazide is removed by haemodialysis. Contact the Poisons Information Centre (131 126) for advice on management.

Presentation

Tablets (oval, biconvex, uncoated, scored on one side), Candesartan HCTZ-GA 16/12.5 (light pink, marked L3/02 on reverse), Candesartan HCTZ-GA 32/12.5 (light yellow, marked L3/04 on reverse), Candesartan HCTZ-GA 32/25 (light pink, marked L3/04 on reverse): 30's (aluminium/ aluminium foil blister pack, HDPE bottle with child resistant PP closure*).
*Not currently marketed in Australia.

Storage

Store below 25°C.

Poison Schedule

S4.