SUMMARY CMI

Antabuse^®

Consumer Medicine Information (CMI) summary

The full CMI on the next page has more details. If you are worried about using this medicine, speak to your doctor or pharmacist.

1. Why am I using Antabuse?

Antabuse contains the active ingredient disulfiram. Antabuse is used to act as a deterrent to alcohol consumption

For more information, see Section 1. Why am I using Antabuse? in the full CMI.

2. What should I know before I use Antabuse

Do not use if you have ever had an allergic reaction to disulfiram or any of the ingredients listed at the end of the CMI.

Talk to your doctor if you have any other medical conditions, take any other medicines, or are pregnant or plan to become pregnant or are breastfeeding.

For more information, see Section 2. What should I know before I use Antabuse? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with Antabuse and affect how it works.

A list of these medicines is in Section 3. What if I am taking other medicines? in the full CMI.

4. How do I use Antabuse

Starting dose: Take between half a tablet (100 mg) and one and a half tablets (300 mg) dissolved in water as a single dose daily for one to two weeks. One tablet daily is the usual maintenance dose.

Your doctor will tell you the exact dosage

More instructions can be found in Section 4. How do I use Antabuse? in the full CMI.

5. What should I know while using Antabuse

For more information, see Section 5. What should I know while using Antabuse? in the full CMI.

6. Are there any side effects?

In the first 2 weeks the following are common side effects, (headache, weakness, acne or skin rash, upset stomach, impotence in men and bad breath.

For more information, including what to do if you have any side effects, see Section 6. Are there any side effects? in the full CMI.

FULL CMI

Antabuse^®

Active ingredient(s): disulfiram

Consumer Medicine Information (CMI)

This leaflet provides important information about using Antabuse. You should also speak to your doctor or pharmacist if you would like further information or if you have any concerns or questions about using Antabuse.

Where to find information in this leaflet:

1. Why am I using Antabuse?
2. What should I know before I use Antabuse?
3. What if I am taking other medicines?
4. How do I use Antabuse?
5. What should I know while using Antabuse?
6. Are there any side effects?
7. Product details

1. Why am I using Antabuse

Antabuse contains the active ingredient disulfiram.
Antabuse is alcohol antagonist. Antabuse inhibits an enzyme, which assists in the breakdown of alcohol in the body. A build-up of a substance called acetaldehyde results. If alcohol is consumed when a patient has received Antabuse the so called "aldehyde reaction" may occur.

Antabuse is designed to act as a deterrent to alcohol consumption.

Antabuse tablets have been approved for the uses listed above. However, your doctor may prescribe this medicine for another use. If you want more information, ask your doctor.

Antabuse tablets are not addictive.

2. What should I know before I use Antabuse?

Warnings

Do not use Antabuse if:

• you are allergic to disulfiram, or any of the ingredients listed at the end of this leaflet. or certain other chemicals (thiuram derivatives) used in pesticides and rubber processing. (See the last section of this leaflet for a full list of ingredients). Signs of allergy include rash, itching, shortness of breath and/or swollen face
• you have heart, liver or kidney disease; organic brain damage, high blood pressure
• you have a mental illness with abnormal thoughts
• you are taking paraldehyde or metronidazole
• the packaging is torn or shows signs of being tampered with
• treating any other complaints unless your doctor says it is safe to do so.
• You continue to consume alcohol. Taking alcohol while using Antabuse results in the ‘aldehyde reaction’. The reaction starts with a flushing from the head downwards involving the face arms and chest. This is accompanied by a feeling of heat, sweating, palpitations, fast heart beat, shortness of breath, hyperventilation and headache. There is a feeling of constriction and irritation in the throat resulting in spasms and coughing. Chest pains may occur. Restlessness or a sense of uneasiness and fear of dying may develop. These symptoms are accompanied by a steep rise in blood pressure, which may be followed by a drop in blood pressure. Flushing is then replaced by the patient becoming pale, weak, feeling dizzy and sick, which turns into violent vomiting and stomach cramps. Other symptoms may include thirst, dizziness, blurred vision, numbness of the hands and feet and the inability to sleep. Severe reactions may affect the heart, and there may be fits, loss of consciousness and death. The reaction usually lasts 2-4 hours and up to several hours in more severe cases.
  Confusion, drowsiness and sleep usually follow. The intensity of the reaction varies with each individual, but generally depends on the amount of Antabuse and alcohol consumed.

If such a reaction is observed, the patient's doctor should be contacted. If the patient is not in hospital or a clinic, an ambulance should be called as the patient requires close monitoring.

You should not take Antabuse until you have not taken any alcohol for 24 hours. If you stop taking Antabuse, you should wait at least one week before consuming alcohol.

Reactions may still occur for up to three weeks after taking Antabuse.

Always check the ingredients to make sure you can use this medicine.

IMPORTANT NOTE

Under all circumstances when taking Antabuse you MUST NOT take alcohol or alcohol-containing preparations e.g. certain cough syrups, sauces, vinegar, tonics, food prepared with wine. You should even avoid the use of after-shave lotions and alcoholic back rubs

Check with your doctor if you:

• have any of the following medical conditions;
  - Diabetes
  - Epilepsy
  - Thyroid problems
  - Heart, kidney or liver disease
  - High blood pressure
  - An allergic skin reaction in you come into contact with certain irritants
  - Asthma
  - Mental illness with abnormal thought
• take any medicines for any other condition

During treatment, you may be at risk of developing certain side effects. It is important you understand these risks and how to monitor for them. See additional information under Section 6. Are there any side effects?

Pregnancy and breastfeeding

Do not use if you are pregnant or intend to become pregnant.

Tell your doctor or pharmacist if you are breastfeeding.

They will advise you on whether you should take Antabuse

3. What if I am taking other medicines?

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

Some medicines may interfere with Antabuse and affect how it works.

• phenytoin and isoniazid.
• sleeping tablets such as Valium.
• medicines which stop blood clotting (warfarin).
• metronidazole and paraldehyde.
• pain killers such as morphine, pethidine, amphetamines and barbiturates.

Check with your doctor or pharmacist if you are not sure about what medicines, vitamins or supplements you are taking and if these affect Antabuse.

4. How do I use Antabuse?

How much to take / use

The following are the usual doses, but your doctor may adjust them to suit your needs:

Starting dose: Take between half a tablet (100 mg) and one and a half tablets (300 mg) dissolved in water as a single dose daily for one to two weeks. Your doctor will tell you the exact dosage. Then go back and see your doctor.

Maintenance dose: Take ONE tablet daily.

Take the tablets in the morning when you wake up. However if you find the tablets make you sleepy you can take them before bedtime. If you are taking Antabuse for a long time, then your doctor will need to do a regular check up. This may include a blood test.

When to take / use Antabuse

Antabuse should be taken in the morning when you wake up. However if you find the tablets make you sleepy you can take them before bedtime.

If you forget to use Antabuse

Antabuse should be used regularly at the same time each day. If you miss your dose at the usual time, do so as soon as you remember, and then go back to taking it as you would normally.

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

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

If you have problems remembering when to take your medicine, ask your pharmacist for some hints

If you use too much Antabuse

If you have taken too much Antabuse you may get drowsy, experience some pain or numbness in the hands and feet which may get worse if not treated

Contact the Poisons Information Centre
(by calling 13 11 26), or
contact your doctor, or
go to the Emergency Department at your nearest hospital.

You should do this even if there are no signs of discomfort or poisoning.

5. What should I know while using Antabse?

Things you should do

Always follow your doctor's instructions carefully and seek your doctor's advice before changing or stopping treatment. Your doctor will be happy to discuss any concerns you may have with your treatment

Always read labels of food and medicines bought to check they contain no alcohol

Things you should not do

Ask your doctor before taking any other medicines. Antabuse can interact with other medicines. Especially check bought medicines from your chemist or supermarket to make sure they contain no alcohol).

Driving or using machines

Be careful before you drive or use any machines or tools until you know how Antabuse affects you.

Antabuse may cause drowsiness or fatigue in some people.

Drinking alcohol

Do not drink alcohol or alcohol containing product. You will suffer from the “aldehyde reaction” which needs immediate medical treatment and may be fatal

Looking after your medicine

Follow the instructions in the carton on how to take care of your medicine properly.

Store it in a cool dry place where the temperature stays below 25°C, away from moisture, heat or sunlight; for example, do not store it:

in the bathroom or near a sink, or
in the car or on window sills.

Keep it where young children cannot reach it.

Getting rid of any unwanted medicine

If you no longer need to use this medicine or it is out of date, take it to any pharmacy for safe disposal.

Do not use this medicine after the expiry date.

6. Are there any side effects?

All medicines can have side effects. If you do experience any side effects, most of them are minor and temporary. However, some side effects may need medical attention.

See the information below and, if you need to, ask your doctor or pharmacist if you have any further questions about side effects.

Less serious side effects

Serious side effects

Tell your doctor or pharmacist if you notice anything else that may be making you feel unwell.

Other side effects not listed here may occur in some people.

Reporting side effects

After you have received medical advice for any side effects you experience, you can report side effects to the Therapeutic Goods Administration online at www.tga.gov.au/reporting-problems. By reporting side effects, you can help provide more information on the safety of this medicine.

Always make sure you speak to your doctor or pharmacist before you decide to stop taking any of your medicines.

7. Product details

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

What Antabuse contains

Do not take this medicine if you are allergic to any of these ingredients.

What Antabuse looks like

Antabuse tablets are white, flat tablets scored and marked with CDC. Antabuse comes in packs of 30 tablets.

(Aust R 70468).

Who distributes Antabuse

Arrotex Pharmaceuticals Pty Ltd
15-17 Chapel St
Cremorne VIC 3121

Ph 1800 195 055

This leaflet was prepared in January 2025.

Published by MIMS March 2025

1 Name of Medicine

Disulfiram.

2 Qualitative and Quantitative Composition

Antabuse: disulfiram 200 mg effervescent tablets.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Antabuse 200 mg effervescent tablets are white, flat tablets, scored and engraved CDC.

4 Clinical Particulars

4.1 Therapeutic Indications

Antabuse tablets are indicated to act as a deterrent to alcohol consumption and an aid in the overall management of selected chronic alcoholic patients involved in an integrated programme of counselling and psychiatry. Only alcoholic patients who are motivated to abstain from drinking and who are undergoing supportive psychotherapeutic treatment, ancillary to a total programme of rehabilitation, should be selected for Antabuse administration.

4.2 Dose and Method of Administration

Antabuse tablets are administered as a single daily dose. They should be taken preferably on waking although, in patients who experience a sedative effect, Antabuse tablets may be taken on retiring. Alternatively, to minimise the sedative effect, the initial dosage may be reduced.

Initial dosage.

Maintenance dosage.

4.3 Contraindications

Antabuse tablets are contraindicated in individuals who are hypersensitive to this drug or to other thiuram derivatives used in pesticides and rubber vulcanisation.
Antabuse tablets are contraindicated in patients with severe myocardial disease, or ischaemic heart disease (coronary artery disease), uncompensated cardiac failure, previous history of CVA, hypertension, in pregnancy, advanced liver and renal disease, and in severe personality disorder, suicidal risk, psychosis/psychotic states, serious organic brain damage.
Under all circumstances, patients receiving Antabuse tablets must not take alcohol or alcohol containing preparations, e.g. certain cough syrups, sauces, vinegar, tonics, foods prepared with wine, and even should avoid the use of aftershave lotions and alcoholic back rubs.
Antabuse tablets should not be administered to patients receiving paraldehyde or metronidazole (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Antabuse tablets should never be administered to a patient who is taking alcohol or is in a state of alcoholic intoxication.
Antabuse tablets should never be administered to patients without their consent and full explanation, and the physician should caution the relatives accordingly. The patient should be fully informed of the disulfiram-ethanol reaction and cautioned against the possible consequences of taking alcohol either surreptitiously or unwittingly.

4.4 Special Warnings and Precautions for Use

Do not administer Antabuse disulfiram tablets until the patient has abstained from alcohol for at least 24 hours.
Patients who stop taking Antabuse tablets should be advised to wait at least 14 days before taking alcohol and that reactions with alcohol may occur for up to three weeks after ingesting disulfiram.
Before initiating treatment it is advised that appropriate examinations should be carried out to establish the suitability of the patient for treatment. Patients must be warned of the unpredictable and potentially severe nature of a disulfiram-alcohol reaction as, in rare cases deaths have been reported following the drinking of alcohol by patients receiving disulfiram. Certain foods, liquid medicines, remedies, tonics, toiletries, perfumes and aerosol sprays may contain sufficient alcohol to elicit a disulfiram-alcohol reaction and patients should be made aware of this. Caution should also be exercised with low alcohol and "non-alcohol" or "alcohol-free" beers and wines, which may provoke a reaction when consumed in sufficient quantities. All personnel involved in the administration of disulfiram to the patient must know that disulfiram should not be given during a drinking episode.

The disulfiram-ethanol reaction.

Management of disulfiram-ethanol reaction.

Other precautions.

Use in the elderly.

Paediatric use.

Effects on laboratory tests.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Disulfiram blocks the metabolism of alcohol and leads to an accumulation of acetaldehyde in the blood stream (see Section 4.4 Special Warnings and Precautions for Use).
The intensity of the disulfiram-alcohol reaction may be increased by amitriptyline. Chlorpromazine while decreasing certain components of the disulfiram-alcohol reaction may increase the overall intensity of the reaction.
Concomitant ingestion of antacids containing divalent cations may reduce absorption. Large doses of ferrous salts similarly block absorption.
Disulfiram may retard the metabolism of certain drugs and thus prolong the duration of action or increase the possibility of clinical toxicity of drugs given concomitantly. The drugs include phenytoin and its congeners, and isoniazid.

Isoniazid.

Phenytoin.

Theophylline.

Benzodiazepines.

Anticoagulants.

Metronidazole.

Paraldehyde.

Miscellaneous.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

4.7 Effects on Ability to Drive and Use Machines

Disulfiram may cause side effects such as drowsiness or fatigue. Patients should make sure they are not affected before driving or operating machinery.

4.8 Adverse Effects (Undesirable Effects)

The principal toxic clinical effects to disulfiram administration alone are drowsiness, lassitude (psychotic reactions); depression, paranoia, schizophrenia, and sensorimotor peripheral neuropathy. Some of these reactions have been known to occur in dosages ranging from 200 mg to 400 mg daily and in associated combined toxicity, e.g. with metronidazole or isoniazid.
The following adverse reactions have been reported. Numbness, tingling, pain or weakness in hands or feet (peripheral neuritis, polyneuritis). Patients who are maintained on disulfiram 500 mg daily tend to develop peripheral neuropathy. This neuropathy improves when disulfiram is discontinued.
Eye pain or tenderness and changes in vision (optic neuritis), encephalopathy, mood and mental changes [psychotic reactions (including mania, depression, paranoia, schizophrenia, reduction in libido)], jaundice, hepatitis, hepatic necrosis, cirrhosis, hepatic cell damage and altered liver function tests, nausea, vomiting have been reported with the administration of Antabuse tablets, although rarely. Drug induced liver injury (fatal cases have been reported).
In addition, impotence, headache, fatigue, halitosis, acneiform eruption, allergic dermatitis, rashes, stomach upset, seizures, have been reported and a metallic or garlic-like aftertaste may be experienced during the first two weeks of therapy. These complaints disappear spontaneously or by reducing dosage.

Reporting suspected adverse effects.

4.9 Overdose

High doses of disulfiram (up to 6 g daily) are relatively nontoxic in man. Disulfiram is toxic to animals only in large doses. The LD₅₀ of a single dose administration in the dog is 3.5 g/kg and in the rat 8.6 g/kg. Death occurs by respiratory arrest, preceded by ascending paralysis, and pathological lesions are seen in the liver, spleen, kidney and CNS, with congestion in the adrenal gland and oedema in the heart muscle. Similar lesions have arisen in animals following chronic administration.
In overdosage situations the stomach should be emptied promptly by induced emesis or lavage. There is no specific therapy for acute overdosage with Antabuse tablets and general symptomatic and supportive measures should be instituted and maintained for as long as necessary (see Section 4.4 Special Warnings and Precautions for Use, The disulfiram-ethanol reaction).
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Clinical trials.

5.2 Pharmacokinetic Properties

Disulfiram is a prodrug.

Absorption.

Distribution.

Metabolism.

Excretion.

5.3 Preclinical Safety Data

Genotoxicity.

Carcinogenicity.

6 Pharmaceutical Particulars

6.1 List of Excipients

The tablets also contain maize starch, povidone, tartaric acid, sodium bicarbonate (equivalent to 6.6 mg sodium per tablet), microcrystalline cellulose, silica colloidal anhydrous, magnesium stearate, polysorbate 20 and purified talc.

6.2 Incompatibilities

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

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Store below 25°C.

6.5 Nature and Contents of Container

Antabuse 200 mg Effervescent tablets in bottles (HDPE) of 30.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Disulfiram is tetraethylthiuram disulphide, which occurs as a cream white, almost odourless, slightly bitter crystalline powder, practically insoluble in water (0.02 g/100 mL), soluble in ethanol and chloroform.

Chemical structure.

CAS number.

7 Medicine Schedule (Poisons Standard)

Schedule 4 - Prescription only medicine.

Summary Table of Changes