Consumer medicine information

ALLERSOOTHE

Promethazine hydrochloride

BRAND INFORMATION

Brand name

Allersoothe

Active ingredient

Promethazine hydrochloride

Schedule

S3

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using ALLERSOOTHE.

What is in this leaflet

This leaflet answers some common questions about Allersoothe.

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

All medicines have risks and benefits. Your pharmacist or doctor has weighed the risks of you taking Allersoothe against the benefits they expect it will have for you.

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

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

What Allersoothe is used for

Allersoothe is an antihistamine used to treat a number of conditions:

  • allergies - allergic contact dermatitis, hives, hayfever, bites and stings
  • respiratory symptoms due to allergies - runny nose
  • nausea and vomiting – motion sickness
  • assists in the management of the symptoms of chicken pox and measles by acting as a sedative
  • for short-term use for sedation on the advice of a pharmacist or doctor - do not use for more than 7-10 days

Antihistamines help reduce allergic symptoms by preventing the effects of a substance called histamine. Histamine is produced by the body in response to foreign substances that the body is allergic to.

Your pharmacist or doctor may have recommended Allersoothe for another reason.

Ask your pharmacist or doctor if you have any questions about this medicine.

Allersoothe should not be used in children under 2 years of age, due to the potential for fatal respiratory depression.

This medicine may affect your ability to drive a car or operate machinery.

Before you take it

When you must not take it

Do not take Allersoothe if you have an allergy to:

  • any medicine containing promethazine hydrochloride
  • any of the ingredients listed at the end of this leaflet

Some of the symptoms of an allergic reaction may include:

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

Do not take this medicine if you have or have had any of the following medical conditions:

  • Glaucoma (high pressure in the eyes)
  • Stomach or duodenal ulcer, or other stomach problems
  • Prostate problems
  • Bladder problems

Do not take Allersoothe if you are also taking monoamine oxidase inhibitors, a type of medicine used to treat depression.

Do not take Allersoothe if you have jaundice.

Do not take this medicine if you are receiving or have received high doses of other CNS depressant medications (for example, drugs that are used to treat anxiety and sleep disorders).

Any person who is unconscious or in a coma must not be treated with Allersoothe.

Do not give Allersoothe to newborn or premature babies.

Do not use for children under two years of age, due to the potential for fatal respiratory depression.

Do not take Allersoothe if you are pregnant or plan to become pregnant. It may affect your developing baby if you take it during pregnancy. Your pharmacist or doctor will discuss the benefits and possible risks of taking the medicine during pregnancy.

Do not take Allersoothe if you are breastfeeding or plan to breastfeed. It passes into the breast milk and there is a possibility that the baby may be affected.

Do not take Allersoothe after the expiry date (EXP) printed on the pack. If you take this medicine after the expiry date has passed, it may note work as well.

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

Before you start to take it

Tell your pharmacist or doctor if you have allergies to:

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

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

  • kidney or liver disease
  • epilepsy
  • cardiovascular disease
  • blood pressure problems
  • breathing problems

Tell your doctor if you plan to have surgery.

Tell your pharmacist or doctor if you take sedatives.

Tell your pharmacist or doctor if you are pregnant or intend to become pregnant. Allersoothe is not recommended for use during pregnancy. If there is a need to consider Allersoothe during your pregnancy, your pharmacist or doctor will discuss with you the benefits and risks of taking it.

Do not take Allersoothe if you are breastfeeding or plan to breastfeed. It passes into the breast milk and there is a possibility that the baby may be affected.

Taking other medicines

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

Some medicines and Allersoothe may interfere with each other. Allersoothe may increase the sedative effect of some drugs. These include:

  • medicines used to treat depression, especially monoamine oxidase inhibitors and tricyclic antidepressants
  • medicines used to help you sleep or relax (sedatives and hypnotics)
  • opioid analgesics, medicines used to treat pain
  • other antihistamines
  • alcohol

These medicines may be affected by Allersoothe or may affect how well it works. You may need different amounts of your medicines, or you may need to take different medicines.

Your pharmacist and doctor will have more information on medicines to be careful with or avoid while taking this medicine.

How to take it

How much to take

Follow all directions given to you by your pharmacist or doctor carefully. They may differ from the information contained in this leaflet.

Allersoothe 25mg tablets are recommended for adults and children 6-12 years only on the advice of a pharmacist of doctor. Allersoothe tablets are not recommended for use in children under 6 years of age - Allersoothe elixir is recommended for children 2-6 years of age. Allersoothe tablets or elixir should not be used in children under 2 years of age.

Allergic Disorder

Adults and children over 12 years: One to three 25mg tablets as a single dose at night, or one to two 10mg tablets, two to three times daily.

Children 6-12 years: One 10mg or one 25mg tablet, or 10 to 25mL of the elixir as a single dose at night, or one 10mg tablet, or 10mL of the elixir, two to three times daily.

Children 2-5 years: 5-15mL of elixir as a single dose at night, or 5mL of elixir, two to three times daily.

Sedation

For short term use on the advice of a pharmacist or doctor.

Adults and children over 12 years: One to three 25mg tablets as a single dose at night.

Children 6-12 years: One 10mg or one 25mg tablet, or 10 to 25mL of the elixir, as a single dose at night.

Children 2-5 years: 5-15mL of elixir as a single dose at night.

Travel Sickness

Adults and children over 12 years: One 25mg tablet.

Children 6-12 years: One 10mg tablet or 10mL of the elixir.

Children 2-5 years: 5mL of elixir.

To be taken the night before travel and repeated after 6 to 8 hours on the following day if required.

Nausea and Vomiting

Adults and children over 12 years: One 25mg tablet every 4 to 6 hours to a maximum daily dose of four 25mg tablets.

Children 6-12 years: One 10mg tablet or 10mL of the elixir, every 4 to 6 hours to a maximum daily dose of two 10mg tablets or 20mL of the elixir.

Children 2-5 years: 5mL of elixir every 4 to 6 hours to a maximum daily dose of 15mL.

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

Do not take more than the recommended dose.

Use in the Elderly

If you are over 65 years of age, talk to you pharmacist or doctor about how much to take.

Elderly patients are more likely to have side effects from taking these medicines.

How to take it

Tablets
Swallow Allersoothe tablets whole with a full glass of water.

Elixir
Measure out the amount of elixir to be taken with a measuring device.

How long to take it

Allersoothe should not usually be taken for more than 10 days in a row. If your symptoms persist, see your pharmacist or doctor for advice.

If you forget to take it

If you are taking Allersoothe for an allergic disorder and you forget to take your bedtime dose, you may need to take your dose in two or three smaller doses during the following day. Check with your pharmacist or doctor.

If you are taking Allersoothe for travel sickness or nausea and vomiting, take your dose as soon as you remember.

If you are taking Allersoothe for sedation, take your dose as soon as you remember.

Be careful because you may still be affected in the morning.

Do not take a double dose to make up for the dose that you missed. This may be harmful.

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

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

If you take too much (overdose)

Immediately telephone your doctor or the Poisons Information Centre (in Australia, call 13 11 26; in New Zealand, call 0800 764 766) for advice or go to Accident and Emergency at the nearest hospital, if you think that you or anyone else may have taken too much Allersoothe.

Do this even if there are no signs of discomfort or poisoning. You may need urgent medical attention.

If you take too much Allersoothe, you may experience:

Adults

  • drowsiness
  • convulsions and/or tremors
  • difficulty breathing
  • unconsciousness
  • acute anxiety
  • hallucinations

Children

  • over - excitement
  • shaky and unsteady movements
  • convulsions and/or tremors
  • hallucinations
  • difficulty breathing
  • unconsciousness
  • high fever

While you are taking it

Things you must do

If you have eczema or a tendency to rheumatism, Allersoothe may cause your skin to be more sensitive to the sun. You should protect your skin from exposure to bright sunlight.

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

If you are about to be started on any new medicine, tell your pharmacist or doctor that you are taking Allersoothe.

If you plan to have surgery that needs a general anaesthetic, tell your doctor or dentist that you are taking this medicine.

If you become pregnant while you are taking this medicine, stop taking it and tell your doctor immediately.

Talk to your pharmacist or doctor if your symptoms do not improve. Your pharmacist or doctor will assess your condition and decide if you should continue to take the medicine.

Things you must not do

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

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

Do not drink alcohol while taking Allersoothe. The sedation effects of alcohol may be increased.

Do not take more than the recommended dose unless your pharmacist or doctor tells you to.

Things to be careful of

Allersoothe is a known sedative and may cause drowsiness in some people. Make sure you know how you react to Allersoothe before you drive a car, operate machinery, or do anything else that could be dangerous if you are drowsy. If this occurs do not drive or operate machinery.

If you have a single dose at bedtime, you may still be affected in the morning.

Avoid alcohol.

Children and the elderly are especially sensitive to the effects of antihistamines.

Side effects

Allersoothe may have unwanted side effects in some 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.

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

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

  • dry mouth, nose & throat
  • stomach upset
  • loss of appetite
  • nausea or vomiting
  • diarrhoea or constipation
  • tiredness or sleepiness
  • restlessness
  • dizziness
  • blurred vision

The above list includes the more common side effects of Allersoothe.

They are usually mild.

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

  • fever
  • difficulty breathing
  • irregular heart beat
  • jaundice - yellow tinge to skin or eyes
  • tremors or convulsions
  • tinnitus - buzzing, hissing, ringing or other persistent noise in the ears
  • seizures (fits)
  • hallucinations
  • nervousness and irritability
  • anxiety
  • twitching or jerking muscles

The above list includes serious side effects that may require medical attention. These side effects are rare.

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

  • wheezing or difficulty breathing
  • swelling of the face, lips, tongue or other parts of the body
  • skin rashes

The above list includes very serious side effects. You may need urgent medical attention or hospitalisation. These side effects are very rare.

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

Do not be alarmed by the lists of possible side effects. You may not experience any of them.

Ask your pharmacist or doctor if you have any questions.

After taking Allersoothe

Storage

Keep your medicine in the pack until it is time to take it. If you take your medicine out of the pack it will not keep as well.

Keep your tablets in a cool dry place where the temperature stays below 30°C

Keep your elixir in a cool dry place, protected from light, where the temperature stays below 30°C

Do not store Allersoothe 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.

Keep it 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.

Disposal

If your pharmacist or doctor tells you to stop taking Allersoothe or if it has passed the expiry date, ask your pharmacist what to do with any left over.

What it looks like

Allersoothe Tablets are available in two strengths:

  • 10mg - Light blue coloured, circular biconvex film coated tablets, plain on both the sides
  • 25mg - Light blue coloured, circular biconvex film coated tablets plain on both sides

Both tablet strengths are available in blister packs of 50 tablets

Allersoothe Elixir is sugar free, alcohol free, banana and vanilla flavoured syrupy liquid.

Allersoothe elixir is available in a 100mL bottle.

Ingredients

Allersoothe Elixir
Active ingredient:

  • promethazine hydrochloride 5 mg / 5 mL.

Inactive ingredients:

  • sodium benzoate
  • propyl gallate
  • citric acid anhydrous
  • vanillin
  • banana flavour
  • glycerol
  • disodium edetate
  • sodium citrate
  • propylene glycol
  • sunset yellow FCF
  • quinoline yellow
  • hydroxyethylcellulose
  • purified water.

Allersoothe tablets
Active ingredient:

  • 10 mg promethazine hydrochloride per tablet
  • 25 mg promethazine hydrochloride per tablet

Inactive ingredients: (for both 10mg and 25mg tablets)

  • lactose
  • hypromellose
  • magnesium stearate
  • methyl cellulose
  • macrogol 6000
  • purified talc
  • titanium dioxide
  • brilliant blue FCF aluminium lake.

Sponsor

AFT Pharmaceuticals Pty Ltd.
Level 1, 296 Burns Bay Rd
Lane Cove
Sydney NSW 2066
AUSTRALIA
Email: [email protected]

Date of preparation

August 2012

Published by MIMS June 2013

BRAND INFORMATION

Brand name

Allersoothe

Active ingredient

Promethazine hydrochloride

Schedule

S3

 

1 Name of Medicine

Promethazine hydrochloride.

2 Qualitative and Quantitative Composition

Allersoothe tablets contain 10 mg or 25 mg promethazine hydrochloride.
Allersoothe Elixir contains 5 mg/5 mL promethazine hydrochloride.

Excipients with known effect.

Tablets: Lactose monohydrate.
Elixir: Sodium benzoate.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Oral tablets.

10 mg or 25 mg: Light blue coloured, circular biconvex film coated tablets, plain on both the sides.

Elixir.

A clear orange syrupy liquid with banana and vanilla flavour.

4 Clinical Particulars

4.1 Therapeutic Indications

Allergies.

Treatment of allergic conditions including some allergic reactions to drugs, urticaria and allergic contact dermatitis, and allergic reactions to insect bites and stings.

Upper respiratory tract.

Relief of excessive secretion in the upper respiratory tract as a result of hayfever and allergic rhinitis.

Nausea and vomiting.

Antiemetic for vomiting from various causes, including postoperative vomiting, irradiation sickness, drug induced nausea and motion sickness.

Sedation.

For short term use in adults under the advice of a doctor or pharmacist. Do not use for more than 7 to 10 consecutive days.

Other.

Promethazine has sedative effects and can be used in the symptomatic management of measles and chicken pox.
Promethazine can be used as a preanaesthetic medication for the prevention and control of postoperative vomiting.

4.2 Dose and Method of Administration

Dose.

Allersoothe should not be used in children under two years of age due to the potential for respiratory depression (see Section 4.3 Contraindications).
Dosage varies according to the condition being treated and the individual's response.
Allersoothe tablets are not recommended for use in children under 6 years of age - Allersoothe Elixir should be considered in children 2-6 years of age. Allersoothe 25 mg tablets are not recommended for children aged 6-12 years unless on pharmacist or medical advice.

Tablets.

Allergic disorders.

Adults.

25 to 75 mg as a single dose at night, or 10 to 20 mg two to three times daily.

Children 6-12 years.

10 to 25 mg as a single dose at night, or 10 mg two to three times daily.

Children 2-5 years.

5 to 15 mg as a single dose at night, or 5 mg two to three times daily.
Sedation.

Adults.

25 to 75 mg as a single dose at night.
Travel sickness.

Adults.

25 mg.

Children 6-12 years.

10 mg.

Children 2-5 years of age.

5 mg.
To be taken the night before travel and repeated after 6 to 8 hours on the following day if required.
Nausea and vomiting.

Adults.

25 mg every 4 to 6 hours to a maximum daily dose of 100 mg.

Children 6-12 years.

10 mg every 4 to 6 hours to a maximum daily dose of 25 mg.

Children 2-5 years.

5 mg every 4 to 6 hours to a maximum daily dose of 15 mg.

Elixir.

Allergic disorder.

Children 6-12 years.

10 to 25 mL as a single dose at night, or 10 mL two to three times daily.

Children 2-5 years.

5 to 15 mL as a single dose at night, or 5 mL two to three times daily.
Travel sickness.

Children 6-12 years.

10 mL.

Children 2-5 years.

5 mL.
To be taken the night before travel and repeated after 6-8 hours on the following day if required.
Nausea and vomiting.

Children 6-12 years.

10 mL every 4 to 6 hours to a maximum daily dose of 20 mL.

Children 2-5 years.

5 mL every 4 to 6 hours to a maximum daily dose of 15 mL.

4.3 Contraindications

Promethazine is contraindicated for use in patients with a history of hypersensitivity to the drug substance, substances of similar chemical structure or hypersensitivity to the other ingredients. Allersoothe Sugar Free Elixir should not be given to patients with allergies to sodium metabisulfite, sodium sulfite or sodium benzoate.
Promethazine is contraindicated for use in:
Children under 2 years of age because of the potential for fatal respiratory depression. Post-marketing cases of respiratory depression, including fatalities, have been reported with the use of promethazine in paediatric patients less than 2 years of age. A wide range of weight-based doses of promethazine have resulted in respiratory depression in these patients (see Section 4.4 Special Warnings and Precautions for Use).
Lactating women.
Patients taking monoamine oxidase inhibitors (MAOls) (see Section 4.5).
Jaundice induced by other phenothiazine derivatives.
Patients who have received high doses of other CNS depressants and/or are comatose.
See Section 4.5 for additional information.

4.4 Special Warnings and Precautions for Use

Caution is advised in patients with:
Cardiovascular disease.
Impaired hepatic function.
Renal failure or impairment.
Acute or chronic respiratory impairment.
Epilepsy.
Hypertensive crisis.
Narrow-angle glaucoma.
Stenosing peptic ulcer.
Symptomatic prostatic hypertrophy.
Bladder neck obstruction.
Pyloroduodenal obstruction.
Promethazine may cause drowsiness and may increase the effects of alcohol. Drowsiness may continue the following day. Those affected should not drive or operate machinery; alcohol should be avoided.
QT interval prolongation has been reported with phenothiazines. See Section 4.5 for additional information.

Use in hepatic impairment.

Use with caution in patient with hepatic impairment.

Use in renal impairment.

Use with caution in patients with renal impairment.

Use in the elderly.

The elderly may experience paradoxical excitation with promethazine. The elderly are more likely to have CNS depressive side effects, including confusion and are more susceptible to the antimuscarinic effects of antihistamines, including hypotension (see Section 4.3 Contraindications).

Paediatric use.

Allersoothe Elixir should not be used in children under 2 years of age, due to the potential for fatal respiratory depression (see Section 4.3 Contraindications).
Allersoothe tablets should not be used in children under 6 years. Allersoothe Elixir should be considered in children 2-6 years of age.
Allersoothe 25 mg tablets are not recommended for children aged 6-12 years unless on pharmacist or medical advice.
Caution should be exercised when administering promethazine to children 2 years of age and older because of the potential for fatal respiratory depression, including central and obstructive apnoea and reduced arousal. Respiratory depression and apnoea, sometimes fatal, are associated with promethazine even if individualised weight-based dosing is used. Concomitant administration of other drugs with respiratory depressant effects should be avoided.
The use of promethazine should be avoided in children and adolescents with signs and symptoms suggestive of Reye's syndrome.
Excessive dosage of antihistamines in children may cause hallucinations, convulsions and sudden death. Children may experience paradoxical excitation with promethazine.
It is recommended that the lowest effective dose of promethazine be used in paediatric patients 2 years of age and older.

Effects on laboratory test.

No data available.

Hypertensive crisis.

Promethazine should be used with caution, if at all, in these patients. Solar dermatitis has been reported following oral doses of Allersoothe in patients with eczema or a tendency to rheumatism.

Epilepsy.

Epileptic patients may experience increased severity of convulsions.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Promethazine may cause drowsiness and may enhance the sedative effects of CNS depressants (including alcohol, barbiturates, hypnotics, opioid analgesics, anxiolytic sedatives and neuroleptics), and have additive antimuscarinic actions with other antimuscarinic drugs (atropine, tricyclic antidepressants). Interactions between promethazine and monoamine oxidase inhibitors and tricyclic antidepressants (TCAs) may prolong and intensify the anticholinergic and CNS depressive effects.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

No data available.
(Category C)
Promethazine, owing to its pharmacological effects, has caused or may be suspected of causing, harmful effects on the human foetus or neonate without causing malformations. These effects may be reversible.
When promethazine has been given in high doses during late pregnancy, promethazine has caused prolonged neurological disturbances in the infant.
Promethazine should be used in pregnancy only if the potential benefits to the patient are weighed against the possible risk to the foetus.
Promethazine is excreted in breast milk. Therefore it should not be used for breastfeeding women.

4.7 Effects on Ability to Drive and Use Machines

Promethazine may cause drowsiness and may increase the effects of alcohol. Drowsiness may continue the following day. Those affected should not drive or operate machinery; alcohol should be avoided.

4.8 Adverse Effects (Undesirable Effects)

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at www.tga.gov.au/reporting-problems.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

CNS effects.

CNS depressive effects of promethazine include sedation and impaired performance (impaired driving performance, poor work performance, incoordination, reduced motor skills, and impaired information processing). Performance may be impaired in the absence of sedation and may persist the morning after a night time dose.
The CNS stimulatory effects of promethazine may include anxiety, hallucinations, appetite stimulation, muscle dyskinesias and activation of epileptogenic foci. High doses of promethazine may cause nervousness, tremor, insomnia, agitation, and irritability.

Anticholinergic effects.

Side effects of promethazine associated with cholinergic blockage include dryness of the eyes, mouth and nose, blurred vision, urinary hesitancy and retention, constipation and tachycardia.

More common reactions.

Gastrointestinal.

Dry mouth, epigastric distress, loss of appetite, nausea, vomiting, constipation, diarrhea.

Nervous system.

Sedation, restlessness, dizziness, lassitude, incoordination, fatigue.

Ocular.

Blurred vision.

Less common reactions.

Cardiovascular.

Tachycardia, bradycardia, faintness.

Dermatological.

Contact dermatitis (topical), photosensitization, urticaria, angioneurotic oedema, pruritus.

Haematological.

Leucopenia, agranulocytosis, aplastic anaemia, thrombocytopenic purpura.

Hepatic.

Jaundice.

Musculoskeletal.

Extrapyramidal symptoms.

Nervous system.

Tinnitus, euphoria, nervousness, insomnia, convulsive seizures, oculogyric crises, excitation, catatonic-like states, hysteria, extrapyramidal symptoms, tardive dyskinesia.

Respiratory.

Marked irregular respiration.

Severe or life threatening reactions.

Agranulocytosis, anaphylaxis.

4.9 Overdose

In case of overdose, immediately contact the Poisons Information Centre (in Australia, call 13 11 26) for advice.
The chief sign of acute poisoning from ingestion of an overdose of Allersoothe is unconsciousness, which is commonly delayed. In addition, convulsions, hallucinations, delirium, acute anxiety, psychotic reactions, extreme hyperaesthesia and hyperalgesia with extensor plantar responses may occur. Anticholinergic action may cause tachycardia, flushed skin, dry mouth and sometimes mydriasis and urinary retention.
In adults, CNS depression is more common, with drowsiness, coma, convulsions, progressing to respiratory failure or cardiovascular collapse.
In infants and children, CNS stimulation predominates over CNS depression causing ataxia, excitement, tremors, psychoses, hallucinations, convulsions and possibly hyperpyrexia, which may be followed by deepening coma and cardiorespiratory collapse.

Treatment.

Similar to that of other phenothiazines. Contact the Poisons Information Centre (in Australia call 13 11 26).
Symptomatic supportive therapy is indicated and maintenance of adequate ventilation should be instituted if necessary.

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Promethazine, a phenothiazine derivative, is a long acting antihistamine with mild atropine-like anticholinergic effects and some antiserotonin effects, and because of its marked effect on the central nervous system (CNS), it acts as an antiemetic, hypnotic, tranquilliser, and a potentiator of anaesthetics, hypnotics, sedatives and analgesics.

Clinical trials.

No data available.

5.2 Pharmacokinetic Properties

Promethazine is well absorbed after oral administration. Peak plasma concentrations are reached 2 to 3 hours after administration by this route, although there is low systemic bioavailability after oral administration, due to high first-pass metabolism in the liver. Promethazine crosses the blood brain barrier and the placenta, and is distributed into breast milk. It is highly bound to plasma proteins (76-93%). Promethazine undergoes extensive metabolism, predominantly to promethazine sulfoxide, and also to N-desmethylpromethazine. It is excreted slowly via the urine and bile, mainly as metabolites. Elimination half-lives of 5 to 14 hours have been reported. The antihistamine action has been reported to be between 4 and 12 hours.

5.3 Preclinical Safety Data

Genotoxicity.

No data available.

Carcinogenicity.

No data available.

6 Pharmaceutical Particulars

6.1 List of Excipients

Elixir.

Sodium benzoate, propyl gallate, citric acid, vanillin, banana flavour 1786, glycerol, disodium edetate, sodium citrate dihydrate, propylene glycol, quinolone yellow, hyetellose, purified water.

Tablets.

Lactose monohydrate, hypromellose, magnesium stearate, methylcellulose, macrogol 6000, purified talc, titanium dioxide, purified water, brilliant blue FCF aluminium lake.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

Tablets.

30 months.

Elixir.

18 months.

6.4 Special Precautions for Storage

Tablets.

Store below 30°C. Protect from light.

Elixir.

Store below 25°C. Protect from light.

6.5 Nature and Contents of Container

Tablets.

10 mg and 25 mg tablets are available in packs of 50s.

Elixir.

100 mL bottle.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of in accordance with local requirements.

6.7 Physicochemical Properties

Promethazine hydrochloride is a white or faintly yellow, practically odourless, crystalline powder. It is very soluble in water, freely soluble in alcohol and in chloroform, and practically insoluble in ether.
Promethethazine hydrochloride has the following structural formula:

CAS number.

58-33-3.

7 Medicine Schedule (Poisons Standard)

Tablets and Elixir: Pharmacist Only Medicine (S3).

Summary Table of Changes