Consumer medicine information

Prochlorperazine AN Tablets

Prochlorperazine maleate

BRAND INFORMATION

Brand name

Prochlorperazine AN Tablets

Active ingredient

Prochlorperazine maleate

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using Prochlorperazine AN Tablets.

What is in this leaflet

This leaflet answers some common questions about Prochlorperazine AN.

It does not contain all the available information that is known about Prochlorperazine AN.

It does not take the place of talking to your doctor or pharmacist.

All medicines have risks and benefits. Your doctor has weighed the risks of you using this medicine against the benefits he/she expects it will have for you.

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

Keep this leaflet with the medicine.

You may need to read it again.

What Prochlorperazine AN is used for

Prochlorperazine AN belongs to a group of medicines called phenothiazines. It helps to correct chemical imbalances in the brain, allowing it to function correctly. These chemicals may also affect the parts of the brain which control nausea (feeling sick) and vomiting.

Prochlorperazine AN is used to treat nausea, vomiting and dizziness due to various causes, including migraine (severe headache).

Your doctor may have prescribed Prochlorperazine AN for another reason.

Ask your doctor if you have any questions about why Prochlorperazine AN has been prescribed to you.

This medicine is available only with a doctor’s prescription.

Prochlorperazine AN is not recommended for use in children (under the age of 2 years or children under 10 kg in weight).

Before you take Prochlorperazine AN

When you must not take it

Do not take Prochlorperazine AN if you have an allergy to:

  • prochlorperazine;
  • the group of medicines called phenothiazines;
  • any of the ingredients listed at the end of this leaflet.

Symptoms of an allergic reaction to Prochlorperazine AN may include:

  • shortness of breath, wheezing or difficulty in breathing;
  • swelling of the face, lips, tongue or other parts of the body;
  • rash, itching or hives on the skin.

You should not take Prochlorperazine AN if you have any of the following medical conditions:

  • shock;
  • disease of the blood with a low number of blood cells;
  • yellowing of the skin and/or eye, also called jaundice.

Prochlorperazine AN must not be given to anyone who is unconscious or in a coma.

Do not take any medicines that cause drowsiness while you are taking Prochlorperazine AN.

Do not take Prochlorperazine AN after the expiry date (EXP) printed on the pack.

If you take this medicine after the expiry date has passed, it may not work as well.

Do not take Prochlorperazine AN if the packaging is torn or shows signs of tampering.

If you are not sure whether you should start taking Prochlorperazine AN, talk to your doctor or pharmacist.

Before you start to take Prochlorperazine AN

Tell your doctor or pharmacist if you have allergies to:

  • any other medicines;
  • any other substances, such as foods, preservatives or dyes.

Tell your doctor if you are pregnant or intend to become pregnant.

Like most phenothiazine medicines, Prochlorperazine AN is not recommended for use during pregnancy. If there is a need to take Prochlorperazine AN during your pregnancy, your doctor will discuss with you the benefits and risks of using it.

Tell your doctor or pharmacist if you are breastfeeding or plan to breastfeed.

It is recommended that you do not breastfeed while taking Prochlorperazine AN, as it is not known whether Prochlorperazine AN passes into breast milk.

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

  • Pheochromocytoma, a rare tumour of the adrenal glands which sit near the kidneys.
  • Parkinson's disease, a disease of the brain affecting movement which causes trembling, rigid posture, slow movement and a shuffling, unbalanced walk.
  • Myasthenia gravis, a disease of the muscles causing drooping eyelids, double vision, difficulty in speaking and swallowing and sometimes muscle weakness in the arms or legs.
  • Kidney problems.
  • Heart and blood vessel problems, low blood pressure, blood clots.
  • Liver disease.
  • Prostate problems.
  • Epilepsy, seizures or fits.
  • Low blood calcium levels.
  • An overactive thyroid gland.
  • Glaucoma, a condition in which there is a build-up of fluid in the eye.
  • Neuroleptic Malignant Syndrome, a reaction to some medicines with a sudden increase in body temperature, extremely high blood pressure and severe convulsions.
  • A reaction to some medicines with uncontrollable twitching or jerking movements of the arms and legs.
  • Dementia.
  • High blood sugar levels.

Tell your doctor if you are about to have any surgery that may require a general anaesthetic.

If you have not told your doctor or pharmacist about any of the above, tell them before you start taking Prochlorperazine AN.

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 and Prochlorperazine AN may interfere with each other.

These include:

  • Some medicines used to control depression or mood swings.
  • Alcohol.
  • Desferrioxamine, a drug used in iron overdose.
  • Procarbazine, an anticancer drug.
  • Some medicines used to control epilepsy.
  • Medicines used to treat Parkinson’s Disease.
  • Anticholinergic medicines which are used to relieve stomach cramps, spasms and travel sickness.
  • Atropine, a medicine which may be used in some eye drops or cough and cold preparations.
  • Some oral medicines used to prevent your blood from clotting.
  • Medicines used to treat high blood pressure and fluid build-up in your body.
  • Other medications such as bepridil, cisapride, sultopride, thioridazine, methadone, erythromycin injection, vincamine injection, halofantine, pentamidine, sparfloxacin, amphotericin B, glucocorticoids or tetracosactides.
  • Anitpsychotics.
  • Certain laxatives.

These medicines may be affected by Prochlorperazine AN or may affect how well it works.

You may need different amounts of your medicine or may need to take different medicines.

Your doctor will advise you.

Your doctor and pharmacist may have more information on medicines to be careful with or avoid while taking Prochlorperazine AN.

How to take Prochlorperazine AN

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

They may differ from the information contained in this leaflet.

If you do not understand the instructions on the pack, ask your doctor or pharmacist for help.

How much to take

Your doctor or pharmacist will tell you how much Prochlorperazine AN you will need to take each day. This depends on your condition and whether or not you are taking any other medicines.

The usual recommended dose for nausea and vomiting is 1 or 2 tablets three to four times daily.

The usual recommended dose for dizziness is 1 or 2 tablets three to four times daily.

How to take it

Swallow the tablets whole with a glass of water. Do not chew the tablets.

When to take it

It does not matter if you take Prochlorperazine AN before or after food.

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

If you have trouble remembering to take your medicine, ask your pharmacist for some hints.

How long to take it

Continue taking Prochlorperazine AN for as long as your doctor tells you.

If you take too much (overdose)

Do not try to vomit.

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

You may need urgent medical attention.

Symptoms of an overdose may include the following:

  • Coma.
  • Restlessness, shaking, muscle twitching, muscle weakness, spasm.
  • Confusion.
  • Excitement or agitation.
  • Low blood pressure.
  • Fast heart beat.
  • Decrease in body temperature.
  • Small pupils in the eye.
  • Difficulty in swallowing or breathing.
  • Blue skin.

Your doctor or pharmacist has information on how to recognise and treat and overdose. Ask your doctor or pharmacist if you have any concerns.

While you are taking Prochlorperazine AN

Tell your doctor immediately if you notice any uncontrolled movements of the tongue, face, mouth or jaw, such as puffing of the cheeks, puckering of the mouth or chewing movements.

These are symptoms of a very rare condition called Tardive Dyskinesia, which may develop in people taking phenothiazine medicine, including Prochlorperazine AN.

The condition is more likely to occur during long term treatment with Prochlorperazine AN, especially in elderly women. In very rare cases, this may be permanent.

Tell any other doctors, dentists and pharmacists who are treating you that you are taking Prochlorperazine AN.

If you are about to be started on any new medicines, tell your doctor, dentist or pharmacist that you are taking Prochlorperazine AN.

If you plan to have surgery that needs a general anaesthetic, tell you doctor or dentist that you are taking Prochlorperazine AN.

If you become pregnant while taking Prochlorperazine AN, tell your doctor immediately.

Things you must not do

Do not give Prochlorperazine AN to anyone else, even if they have the same condition as you.

Do not take Prochlorperazine AN to treat any other complaints unless your doctor or pharmacist tells you to.

Do not stop taking Prochlorperazine AN, or lower the dosage, even if you are feeling better, without checking with your doctor.

If you stop taking Prochlorperazine AN suddenly, your condition may worsen or your chance of getting an unwanted side effect may increase. To prevent this, your doctor may gradually reduce the amount of Prochlorperazine AN you take each day before stopping completely.

Your doctor may check your eyes, thyroid, lipid and blood glucose levels.

Tell your doctor if, for any reason, you have not taken your medicine exactly as prescribed.

Your doctor may think it is not working effectively and change your treatment unnecessarily.

Things to be careful of

Be careful driving or operating machinery until you know how Prochlorperazine AN affects you.

As with other medicines, Prochlorperazine AN may cause dizziness, lightheadedness, tiredness, drowsiness in some people. Make sure you know how you react to Prochlorperazine AN before you drive a car, operate machinery, or do anything else that could be dangerous if you are dizzy or light-headed. If this occurs do not drive. If you drink alcohol, dizziness or lightheadedness may be worse.

If Prochlorperazine AN makes you feel light-headed, dizzy or faint, be careful when getting up from a sitting or lying position. Getting up slowly may help. Be careful when drinking alcohol while taking Prochlorperazine AN.

Combining Prochlorperazine AN and alcohol can make you more sleepy, dizzy or light-headed.

Your doctor may suggest you avoid alcohol while you are being treated with Prochlorperazine AN.

If outdoors, wear protective clothing and use at least a 15+ sunscreen.

Prochlorperazine AN may cause your skin to be much more sensitive to sunlight than it is normally. Exposure to sunlight may cause a skin rash, itching, redness or even severe sunburn. If your skin does appear to be burning, tell your doctor.

Make sure you keep cool in hot weather and keep warm in cool weather.

Prochlorperazine AN may affect the way your body reacts to temperature changes.

Side effects

Tell your doctor or pharmacist as soon as possible if you do not feel well while you are taking Prochlorperazine AN.

Prochlorperazine AN helps most people with nausea, vomiting and dizziness, but it may have unwanted side effects in a few people.

All medicines can have side effects.

Sometimes they are serious, most of the time they are not. You may need medical treatment if you get some of the side effects. If you are over 65 years of age you may have an increased chance of getting side effects.

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

If you get any side effects, do not stop taking Prochlorperazine AN without first talking to your doctor or pharmacist.

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

  • Constipation.
  • Dry mouth.
  • Drowsiness.
  • Restlessness.
  • Trembling, rigid posture, mask-like face, slow movements and a shuffling, unbalanced walk.
  • Twitching.
  • Blurred vision.

The following side effects are less common:

  • Low blood pressure.
  • Changes in heart beats.
  • Swelling of the hands, ankles or feet.
  • Skin rash.
  • For females, unusual secretion of breast milk, irregular periods.
  • For males, breast enlargement, difficulty in ejaculating.
  • Severe pain in the stomach with bloating, cramps and vomiting.
  • Difficulty passing urine.
  • Yellowing of the skin and/or eyes.
  • Headache.
  • Insomnia.
  • Seizures.
  • Difficulty in breathing.
  • High blood sugar levels.

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

  • Unusual muscle tone or spasms causing distortion of the body in children.

These are very serious side effects.

You may need urgent medical attention or hospitalization.

All of these side effects are very rare.

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

Do not be alarmed by this list of possible side effects. You may not experience any of them.

After using Prochlorperazine AN

Storage

Keep Prochlorperazine AN tablets in a cool dry place where the temperature stays below 25°C. Protect from light.

Keep your Prochlorperazine AN in the pack until it is time to take them.

If you take the tablets out of the pack, they may not keep well.

Do not store Prochlorperazine AN or any other medicine in the bathroom or near a sink.

Do not leave it in the car on hot days or on window sills.

Heat and dampness can destroy some medicines.

Disposal

If your doctor tells you to stop taking Prochlorperazine AN, 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

Prochlorperazine AN tablets are white/off white, circular uncoated tablets, marked with "5" on one side.

Prochlorperazine AN are available in packs of 25 tablets. AUST R 158413

Ingredients

Active Ingredient:
Each tablet contains prochlorperazine maleate 5 mg.

Inactive Ingredients:

  • Lactose
  • Maize starch
  • Purified water
  • Colloidal anhydrous silica
  • Magnesium stearate

Name and Address of the Sponsor

Scentia Pharmaceuticals Pty Ltd
8 - 12 Ordish Road
Dandenong South,
VIC - 3175
Australia

Date of Preparation

January 2014

Doc ID: 90.AN.M.1.0

BRAND INFORMATION

Brand name

Prochlorperazine AN Tablets

Active ingredient

Prochlorperazine maleate

Schedule

S4

 

Name of the medicine

Prochlorperazine maleate.

Excipients.

Lactose, maize starch, purified water, anhydrous colloidal silica and magnesium stearate.

Description

Chemical name: 2-chloro-10-[3-(4-methylpiperazin-1-yl)propyl]-10H-phenothiazide bis[hydrogen (Z)-butenedioate]. Molecular formula: C20H24CIN3S.2C4H4O4. MW: 606.2. CAS: 84-02-6. Prochlorperazine maleate contains 62% of the active base prochlorperazine. It is an odourless, nonhydroscopic, white or almost white, fine granular powder, which becomes coloured on exposure to light. It is sparingly soluble (about 0.1%) in water, ethanol or methanol and is insoluble in ether or chloroform.

Pharmacology

Prochlorperazine is a phenothiazine with a piperazine moiety in the side chain. It possesses strong antiemetic and antipsychotic activity with less sedative action than chlorpromazine.

Pharmacodynamics.

As with other phenothiazines, prochlorperazine has actions on several neurotransmitter systems.
1. Antidopamine action, which probably contributes to both the therapeutic effect and unwanted effects including extrapyramidal disorders and endocrine disturbances.
2. α-Adrenoreceptor antagonism, which contributes to cardiovascular side effects such as orthostatic hypotension and reflex tachycardia.
3. Potentiation of noradrenaline by blocking its reuptake into nerve terminals.
4. Weak anticholinergic action.
5. Weak antihistamine action.
6. Weak serotonin antagonism.
Prochlorperazine also has an effect on temperature control and blocks conditioned avoidance responses.

Pharmacokinetics.

There are few published data on prochlorperazine pharmacokinetics in the human. Most studies have been done in rats and dose levels do not correspond to those used in clinically and metabolic pathways may differ. Similar overall pharmacokinetic patterns however would occur in the human.
Prochlorperazine is well absorbed from the GI tract in rats but absorption is slowed in repeatedly treated animals. The drug is widely distributed to tissues including the brain, fat, kidney, heart and skin and is stored in reticuloendothelial tissues. Phenothiazines are metabolized primarily in the liver and are subject to enterohepatic circulation. Excretion is mainly in the faeces. Only a very small amount (approx. 0.1%) of prochlorperazine and its metabolites are excreted in the first 24 hours in the urine and the drug may continue to be excreted in the urine for up to 3 weeks after cessation of long-term therapy. The elimination half-life is approximately 24 hours, presumably due to its enterohepatic circulation.

Indications

Nausea and vomiting due to various causes including migraine; vertigo due to Meniere's syndrome, labyrinthitis and other causes.

Contraindications

Circulatory collapse, central nervous system depression (coma or drug intoxication); previous history of a hypersensitivity reaction (e.g. jaundice or blood dyscrasia) to phenothiazines, especially to prochlorperazine; bone marrow depression.

Precautions

Prochlorperazine should be avoided in patients with renal dysfunction, Parkinson's disease, hypothyroidism, phaeochromocytoma, myasthenia gravis and prostate hypertrophy.

Hypotension.

The autonomic side effects of the piperazine derivatives are less troublesome than those of other phenothiazines, however care should be taken if prochlorperazine is used in the elderly or in patients undergoing surgery with spinal anaesthesia.

Epileptics.

Piperazine derivatives are also less epileptogenic than other phenothiazines, but care should still be exercised in epileptic patients.

Anticholinergic effects.

Prochlorperazine can cause problems due to anticholinergic effects, especially in the elderly (urinary difficulties, constipation and precipitation of acute narrow angle glaucoma), but to a lesser extent than with other phenothiazines.

Hypocalcaemia.

It appears from a study of 5 hypocalcaemic patients with hypoparathyroidism that such patients are prone to acute dystonic reactions with prochlorperazine.

Sedative effect.

Prochlorperazine may impair mental and physical activity especially during the first few days of therapy. Patients should be warned about activities requiring alertness.

Antiemetic effects.

The antiemetic effects of prochlorperazine may mask signs of overdosage of toxic drugs or obscure the diagnosis of conditions such as intestinal obstruction, brain tumour.

Reye's syndrome.

The extrapyramidal symptoms which can occur secondary to prochlorperazine may be confused with the central nervous system signs of an undiagnosed primary disease responsible for the vomiting, e.g. Reye's syndrome or other encephalopathy. The use of prochlorperazine and other potential hepatotoxins should be avoided in children and adolescents whose signs and symptoms suggest Reye's syndrome.

Hypothermia.

Severe hypothermia may occur during swimming in cold water or in patients receiving antipyretic therapy.

Liver disease.

Caution should be used in patients with existing liver disease due to the extensive hepatic metabolism of prochlorperazine. A past history of jaundice resulting from phenothiazine therapy indicates a hypersensitivity reaction and there is a likelihood of cross sensitivity to other phenothiazines.

Tardive dyskinesia.

Tardive dyskinesia may develop in patients on antipsychotic drugs. The disorder consists of repetitive involuntary movements of the tongue, face, mouth or jaw (e.g. protrusion of the tongue, puffing the cheeks, puckering of the mouth, chewing movements). The trunk and limbs are less frequently involved. It has been reported that fine vermicular movements of the tongue may be an early sign of the syndrome.
Both the risk of developing the syndrome and the likelihood that it will become irreversible are believed to increase as the duration of treatment and the total cumulative dose of the drug increases. Less commonly, the syndrome can develop after relatively brief treatment periods at low doses. The risk seems to be greater in elderly patients, especially females.
The syndrome may become clinically recognizable either during treatment, upon dosage reduction, or upon withdrawal of treatment. The dosage of antipsychotic drug should be reduced periodically (if clinically possible) and the patient observed for signs of the disorder, since the syndrome may be masked by a higher dose. In patients requiring long-term treatment, the smallest dose and the shortest duration of treatment producing a satisfactory clinical response should be sought.
There is no known effective treatment for tardive dyskinesia. Antiparkinsonian agents usually do not alleviate symptoms. It is suggested that antipsychotic agents be discontinued if symptoms of tardive dyskinesia appear.

Neuroleptic malignant syndrome.

A potentially fatal syndrome called neuroleptic malignant syndrome has been reported in association with antipsychotic drugs. The syndrome is characterized by muscular rigidity, fever, hyperthermia, altered consciousness and autonomic instability (e.g. tachycardia, labile blood pressure, profuse sweating, dyspnoea).
The management of neuroleptic malignant syndrome should include immediate discontinuation of antipsychotic drugs, intensive monitoring and treatment of symptoms, and treatment of any associated medical problems.

QT interval.

Very rare cases of QT interval prolongation have been reported with prochlorperazine. Neuroleptic phenothiazines may potentiate QT interval prolongation which increases the risk of onset of serious ventricular arrhythmias of the torsades de pointes type, which is potentially fatal (sudden death). QT prolongation is exacerbated, in particular, in the presence of bradycardia, hypokalaemia, and congenital or acquired (i.e. drug induced) QT prolongation. If the clinical situation permits, medical and laboratory evaluations should be performed to rule out possible risk factors before initiating treatment with a neuroleptic agent and as deemed necessary during treatment (see Adverse Effects).

Cerebrovascular events.

An increased risk of cerebrovascular events has been reported in elderly patients with dementia treated with atypical antipsychotic drugs. An increase in the risk of cerebrovascular events with other antipsychotic drugs or other populations of patients cannot be excluded. Prochlorperazine should therefore be used with caution in patients with stroke risk factors.

Thromboembolism.

Cases of venous thromboembolism, sometimes fatal, have been reported with antipsychotic drugs. Therefore, prochlorperazine should be used with caution in patients with risk factors for thromboembolism (see Adverse Effects).

Elderly patients with dementia.

Elderly patients with dementia related psychosis treated with antipsychotic drugs are at an increased risk of death. Although the causes of death in clinical trials with atypical antipsychotics were varied, most of the deaths appeared to be either cardiovascular (e.g. heart failure, sudden death) or infectious (e.g. pneumonia) in nature. Observational studies suggest that, similar to atypical antipsychotic drugs, treatment with conventional antipsychotic drugs may increase mortality. The extent to which the findings of increased mortality in observational studies may be attributed to the antipsychotic drug as opposed to some characteristic(s) of the patients is not clear.

Hyperglycaemia.

Hyperglycaemia or intolerance to glucose has been reported in patients treated with prochlorperazine. Patients with an established diagnosis of diabetes mellitus or with risk factors for the development of diabetes who are started on prochlorperazine, should get appropriate glycaemic monitoring during treatment (see Adverse Effects).

Use in pregnancy.

(Category C)
When given in high doses during late pregnancy, phenothiazines have caused jaundice, hyper-reflexia, hyporeflexia or prolonged extrapyramidal disturbances in the child. There is inadequate evidence of the safety of prochlorperazine in human pregnancy but it has been widely used for many years without apparent ill consequence. There is evidence of harmful effects in animals. Like other drugs, it should be avoided in pregnancy unless the physician considers it essential. Neuroleptics may occasionally prolong labour and at such a time should be withheld until the cervix is dilated 3-4 cm. Possible adverse effects on the foetus include lethargy or paradoxical hyperexcitability, tremor and a low Apgar score.

Use in lactation.

Trace amounts of another phenothiazine, chlorpromazine, have been detected in breast milk, but there is no information available for prochlorperazine. Consequently, it is not known whether it is excreted in breast milk or whether it has a harmful effect on the newborn. Therefore, prochlorperazine is not recommended for nursing mothers unless the expected benefits outweigh any potential risk.

Use in children.

Prochlorperazine is not recommended for use in children under 10 kg in weight or under 2 years of age as acute extrapyramidal reactions are more likely to occur.

Interactions

Caution is required with the use of the following medicines due to the risk of QT prolongation (see Precautions).
CIass Ia antiarrhythmic agents such as quinidine and disopyramide.
Class III antiarrhythmic agents such as amiodarone and sotalol.
Other medications such as bepridil, cisapride, sultopride, thioridazine, methadone, intravenous erythromycin, intravenous vincamine, halofantrine, pentamidine, sparfloxacin.
Medicines which induce bradycardia, such as bradycardia inducing calcium channel blockers (diltiazem, verapamil), beta-blockers, clonidine, guanfacine, digitalis.
Medicines which can cause hypokalaemia, such as diuretics, stimulant laxatives, intravenous amphotericin B, glucocorticoids, tetracosactides.
Other antipsychotics.
Prochlorperazine may enhance the CNS depressant effects of alcohol and other depressant drugs, and potentiate the anticholinergic effects of atropinic agents and tricyclic antidepressants.
Simultaneous administration of desferrioxamine and prochlorperazine has been observed to induce a transient metabolic encephalopathy characterized by loss of consciousness for 48-72 hours.
Procarbazine has been reported to potentiate the extrapyramidal side effects encountered with the use of prochlorperazine. Phenothiazines have been reported both to impair and increase metabolism of phenytoin, with uncertain clinical significance. Patients on levodopa should not be given phenothiazines because the two drugs are physiologically antagonistic.
Phenothiazines can diminish the effect of oral anticoagulants.
Thiazide diuretics may accentuate the orthostatic hypotension that may occur with phenothiazines.
Antihypertensive effects of guanethidine and related compounds may be counteracted when phenothiazines are used concomitantly.
Concomitant administration of propranolol with phenothiazines results in increased plasma levels of both drugs. Phenothiazines may lower the convulsive threshold; dosage adjustments of anticonvulsants may be necessary.

Adverse Effects

The following reactions have been reported for prochlorperazine or phenothiazines in general.

More common reactions.

Gastrointestinal.

Constipation, dry mouth.

Nervous system.

Drowsiness, akathisia, parkinsonism, (with dyskinesia, tremor and rigidity).

Ocular.

Blurred vision.

Less common reactions.

Biochemical abnormalities.

Elevated serum levels of bilirubin and hepatic enzymes may occur if the patient develops cholestatic jaundice.

Cardiovascular.

Hypotension, peripheral oedema, cardiac arrhythmias, ECG changes, QT interval prolongation. There have been isolated reports of sudden death, with possible causes of cardiac origin (see Precautions), as well as cases of unexplained sudden death, in patients receiving neuroleptic phenothiazines. Cases of venous thromboembolism, including cases of pulmonary embolism, sometimes fatal, and cases of deep vein thrombosis have been reported with antipsychotic drugs (see Precautions).

Dermatological.

Dermatitis or contact dermatitis, maculopapular eruptions, erythema multiforme, urticaria, photosensitivity, abnormal pigmentation.

Endocrine.

Endocrine disturbances including elevated prolactin levels, hyperglycaemia, hypoglycaemia, menstrual irregularities, galactorrhoea, gynaecomastia.

Gastrointestinal.

Paralytic ileus.

Genitourinary.

Urinary retention, inhibition of ejaculation.

Haematological.

Agranulocytosis, atypical lymphocytes, thrombocytopenia, leucopenia, aplastic anaemia.

Hepatic.

Cholestatic jaundice, liver damage.

Nervous system.

Acute dystonic reactions, seizures, EEG changes, headache, insomnia, catatonia, hyperpyrexia.

Ocular.

Pigmentary retinopathy.

Psychiatric.

Activation of psychotic symptoms.

Respiratory.

Respiratory depression.
In postmarketing surveillance cases of hyperglycaemia or intolerance to glucose have been reported with antipsychotic phenothiazines (see Precautions).

Serious or life threatening reactions

Prochlorperazine can cause very serious acute dystonic reactions in children leading to cyanosis from laryngospasm, apnoea requiring artificial ventilation, life threatening tetanus-like syndromes, coma and even death. These reactions can occur with a single therapeutic dose. For treatment, see Overdosage. Also, long-term phenothiazines therapy has been associated with ECG changes and life threatening cardiac arrhythmias.

Dosage and Administration

Nausea and vomiting.

Adults.

Dosage should be adjusted to suit the response of the individual, beginning with the lowest recommended dosage.

Oral.

5 or 10 mg two or three times daily.

Acute.

20 mg at once, followed, if necessary by 10 mg two hours later.

Children.

(See Precautions, Use in children).
If it is considered unavoidable to use prochlorperazine for a child, the dosage is 250 microgram/kg bodyweight two or three times a day.
Prochlorperazine has been associated with dystonic reactions particularly after a cumulative dosage of 500 microgram/kg. It should therefore be used cautiously in children.
Prochlorperazine is not recommended for children weighing less than 10 kg.

Vertigo in Meniere's syndrome.

Adults.

Oral.

5 to 10 mg three to four times daily.
Dosage may be reduced gradually after several weeks to a maintenance dosage of 5 to 10 mg daily.

Children.

Oral.

Same as for nausea and vomiting.

Geriatric.

In general, dosages in the lower range are sufficient for most elderly patients. Since they are especially susceptible to hypotension and extrapyramidal reactions, such patients should be observed closely. Dosage should be increased more gradually in elderly patients.

Impaired liver function.

Since prochlorperazine is extensively metabolized by the liver, dosage reduction may be necessary.

Overdosage

Symptoms.

Overdosage with phenothiazines may cause CNS depression progressing from drowsiness to coma with areflexia. Patients with early or mild intoxication may experience restlessness, confusion and excitement. Other symptoms include hypotension, tachycardia, hypothermia, pupillary constrictions, restlessness, tremor, muscle twitching, spasm or rigidity, convulsions, muscular hypotonia, difficulty in swallowing or breathing, cyanosis, and respiratory and/or vasomotor collapse, possible with sudden apnoea. There is no information available regarding lethal dose in man.

Treatment.

1. Acute dystonic reactions.

Intramuscular benztropine (or another antiparkinsonian agent) should be given immediately (adults: 1 to 2 mg i.m.; children: 0.2 mg i.m. initially with increments if necessary).

2. Overdosage.

Emesis should not be induced, not only because the antiemetic action of prochlorperazine prevents the effect of the emetic agent, but also because the sedative and extrapyramidal side effects increase the risk of pulmonary aspiration should vomiting occur. Management is generally supportive with particular attention to the possibility of obstructed ventilation, severe hypotension, hypothermia, cardiac arrhythmias, convulsions and prolonged deep sedation. Acute dystonic reactions usually occur early (if at all); treatment is with anticholinergic agents, as above.
Adrenaline must not be used as it may cause a paradoxical further lowering of blood pressure.
Contact the Poisons Information Centre on 131 126 for advice on management of overdosage.

Presentation

Tablets, 5 mg (white to off white, circular, uncoated, marked 5 on one side): 14's*, 25's, 28's*, 56's*, 84's*, 100's*, 250's* (PVC/PVDC/Al blister pack, AUST R 158413).
*Not currently marketed in Australia.

Storage

Store below 25°C and protect from light.

Poison Schedule

S4.