Consumer medicine information

What is in this leaflet

This leaflet answers some common questions about Paraldehyde Injection. It does not contain all the available information. It does not take the place of talking to your doctor.

All medicines have risks and benefits. Your doctor has weighed the risks of you being given Paraldehyde Injection against the benefits they expect it will have for you.

If you have any concerns about being given this medicine, ask your doctor.

Keep this leaflet in a safe place. You may need to read it again.

What Paraldehyde Injection is used for

Paraldehyde Injection is used to treat convulsions, seizures and fits. It is also used as a sedative or to induce sleep.

It is only recommended for use when other treatments do not work or are not appropriate for the condition to be treated.

This medicine belongs to a group of medicines called sedatives and hypnotics.

Ask your doctor if you have any questions about why this medicine has been prescribed for you. Your doctor may have prescribed it for another reason.

This medicine is addictive.

Before you are given Paraldehyde Injection

When you must not be given it

You should not be given Paraldehyde Injection if you have an allergy to:

• any medicine containing paraldehyde
• any of the ingredients listed at the end of this leaflet
• any other similar medicines.

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.

You should not be given this medicine if you have severe liver disease.

You should not be given this medicine if you have lung disease.

You should not be given this medicine if you are pregnant. It may affect your developing baby if you are given it during pregnancy.

Do not breast-feed if you are being given this medicine. The active ingredient in Paraldehyde Injection passes into breast milk and there is a possibility that your baby may be affected.

You should not be given this medicine if the solution is discoloured, cloudy, turbid, or a precipitate is present. The solution is normally a clear, colourless to pale yellow liquid.

You should not be given this medicine after the expiry date printed on the pack or if the packaging is torn or shows signs of tampering. If you are given this medicine after the expiry date has passed, it may not work as well.

If you are not sure whether you should be given this medicine, talk to your doctor.

Before you are given it

Tell your doctor if you have ever received Paraldehyde Injection before.

Tell your doctor if you have allergies to any other medicines, foods, preservatives or dyes.

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

• heart disease
• asthma
• liver disease.

If you have not told your doctor about any of the above, tell them before you are given Paraldehyde Injection.

Taking other medicines

Tell your doctor if you are taking any other medicines, including any that you get without a prescription from your pharmacy, supermarket, health food shop, naturopath or herbalist. Some medicines and Paraldehyde Injection may interfere with each other. These include:

• alcohol
• barbiturates, medicines used for sedation or to treat seizures
• disulfiram, a medicine used to treat alcohol withdrawal.

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

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

How Paraldehyde Injection is given

Paraldehyde Injection must only be given by a doctor, nurse or other trained person.

Paraldehyde Injection is given by injection into a muscle usually the buttocks. No more than 5 mL should be injected into the same spot.

Your doctor will decide what dose of Paraldehyde Injection you will receive and for how long you will receive it. This depends on your medical condition and other factors, such as your weight.

If you are given too much (overdose)

Paraldehyde Injection must only be given by a doctor, nurse or other trained person so an overdose is not likely to occur.

Immediately telephone your doctor or go to the Emergency Department at the nearest hospital if you think that too much Paraldehyde Injection has been given.

Symptoms of an overdose may include:

• rapid breathing
• cloudy urine, decreased urination
• slow heartbeat
• general weakness.

Contact the Poisons information centre on 13 11 26 for further advice on overdose management.

While you are being given Paraldehyde Injection

Things you must do

If you are about to be started on any new medicine, remind your doctor and pharmacist that you have been given Paraldehyde Injection.

Tell any other doctors, dentists, and pharmacists who treat you that you have been given this medicine.

If you are going to have surgery, tell the surgeon or anaesthetist that you have been given this medicine. It may affect other medicines used during surgery.

If you become pregnant while being given this medicine, tell your doctor immediately.

Things you must not do

Do not drive or operate machinery after being given Paraldehyde Injection. This medicine causes drowsiness. Do not drive, operate machinery or do anything else that could be dangerous.

Do not drink alcohol after being given this medicine. If you drink alcohol, the effects of this medicine may be worse.

Things to be careful of

If you feel light-headed, dizzy or faint when getting out of bed or standing up, get up slowly. Standing up slowly, especially when you get up from chairs, will help your body get used to the change in position and blood pressure. If this problem continues or gets worse, talk to your doctor.

This medicine should not be stopped suddenly. If this medicine is stopped suddenly it may have unwanted side effects such as hallucinations, sweating, tremors, restlessness and mental confusion. If possible your doctor will gradually reduce the amount you are given before stopping the medicine completely.

Side effects

Tell your doctor or nurse as soon as possible if you do not feel well while you are being given Paraldehyde Injection.

This medicine helps most people with seizures 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 attention if you get some of the side effects.

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

Ask your doctor to answer any questions you may have.

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

• skin rashes
• dizziness
• muscle cramps or tremors
• unusual sweating.

The above list includes the more common side effects of your medicine.

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

• pain, blistering or swelling at the injection site
• numbness at or near the injection site
• swelling and redness along a vein
• breathlessness, which may be very severe and usually worsens on lying down
• bluish discolouration of the skin
• nausea
• swelling or oedema
• severe stomach cramps
• confusion or agitation
• symptoms of hepatitis
  - nausea, vomiting, loss of appetite
  - yellowing of the skin and eyes
  - itching
  - fever
  - dark coloured urine.

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

Tell your doctor or nurse if you notice anything that is making you feel unwell.

Other side effects not listed above may also occur in some people.

Some of these side effects can only be found when your doctor does tests from time to time to check your progress.

After being given Paraldehyde Injection

Storage

Paraldehyde Injection will be stored in the surgery, pharmacy or ward of a hospital. The injection is kept in a dry place where the temperature stays below 25°C. It is protected from light.

Paraldehyde Injection should not be kept in the refrigerator. If crystallised, Paraldehyde Injection should be warmed gently.

Paraldehyde Injection will be opened for use on you. It will be used only once and then it will be discarded. It will never be stored after it is opened, nor used for more than one person.

Product description

What it looks like

Paraldehyde Injection is a clear, colourless to pale yellow solution in a clear glass vial.

Paraldehyde Injection is available in a 5 mL vial.

Ingredients

Paraldehyde Injection contains 100% paraldehyde as the active ingredient.

It also contains:

• hydroquinine as an antioxidant.

This medicine does not contain lactose, sucrose, gluten, tartrazine or any other azo dyes, alcohol or preservatives.

Manufacturer

Paraldehyde Injection is made and supplied in Australia by:

Phebra Pty Ltd
19 Orion Road
Lane Cove West, NSW 2066
Australia

Distributor

Paraldehyde Injection is distributed in New Zealand by:

AFT Pharmaceuticals Ltd
PO Box 33-203 Takapuna
Auckland, New Zealand

Paraldehyde Injection 5 mL vial AUST R 160612
Phebra product code-INJ153

This leaflet was prepared in June 2015.

Phebra and Phi symbol are trademarks of Phebra Pty Ltd, 19 Orion Road, Lane Cove West, NSW 2066, Australia.

Published by MIMS October 2016

Name of the medicine

Paraldehyde.

Excipients.

Description

Chemical name: 2,4,6 -trimethyl -1,3,5 -trioxane. Molecular formula: (C₂H₄O)₃. MW: 132.2. CAS: 123-63-7. It is a colourless or pale yellow transparent liquid, with a strong odour and disagreeable burning taste. Paraldehyde is soluble 1 in 10 of water, but is only soluble 1 in 17 in boiling water. It is miscible with alcohol, chloroform, ether and volatile oils. Paraldehyde solidifies to form a crystalline mass at low temperatures, but can be liquefied by warming. Paraldehyde is a cyclic trimer of acetaldehyde.

Pharmacology

Pharmacodynamics.

Pharmacokinetics.

Absorption.

Distribution.

Metabolism.

Excretion.

Indications

Paraldehyde has been used as a sedative and hypnotic in a variety of clinical situations, although it has been largely replaced by safer and/or more effective agents. It may also be used in the treatment of convulsive episodes arising from tetanus, status epilepticus and poisoning by convulsive drugs, when other agents are inappropriate or ineffective. Paraldehyde may be effective in reducing the anxiety associated with withdrawal from drugs such as narcotics or barbiturates, as well as in the management of acute agitation or delirium tremens due to alcohol withdrawal. Paraldehyde is only recommended for use in these conditions when other treatments are ineffective or deemed inappropriate.

Contraindications

Paraldehyde is contraindicated in patients hypersensitive to the drug.
Paraldehyde is contraindicated in patients with severe hepatic insufficiency.
Paraldehyde should not be used for obstetric anaesthesia, as the drug diffuses across the placenta and has been known to cause respiratory depression in neonates.
Paraldehyde Injection BP is contraindicated in patients with bronchopulmonary disease, as unmetabolised paraldehyde (11 to 28%) is excreted via exhalation.

Precautions

Use only freshly opened vials. Paraldehyde Injection BP must not be used if the container has been opened as it decomposes on storage. The administration of partly decomposed paraldehyde is dangerous as it may cause metabolic acidosis. Deaths from corrosive poisoning have been reported following the use of decomposed paraldehyde. It must not be used if it has a brownish colour or a sharp penetrating odour of acetic acid.
Due to the solvent action of paraldehyde, plastic syringes must not be used. Contact between paraldehyde and rubber should be avoided.
Avoid contact with the skin, eyes and clothing.
Prolonged use of paraldehyde may lead to dependence of the barbiturate alcohol type, especially in alcoholics. Prolonged use may also produce tolerance and physical and/or psychological dependence on the drug. Sudden withdrawal of paraldehyde from physically dependent persons may cause delirium tremens and hallucinations. In dependent persons, the drug should be withdrawn slowly.
Toxic hepatitis, nephrosis and metabolic acidosis have been reported following prolonged use of paraldehyde (see Adverse Effects).
Paraldehyde Injection BP should not be administered subcutaneously because it is irritating to tissues.
Avoid intramuscular injection near nerve trunks as this may cause severe and permanent nerve damage (see Adverse Effects).
Intravenous administration is extremely hazardous since it may cause pulmonary oedema and haemorrhage, hypotension and cardiac dilatation, and circulatory collapse. Thrombophlebitis is also associated with intravenous administration. Paraldehyde should be used cautiously, if at all, in patients with cardiovascular disease, asthma or other bronchopulmonary disease.
Impaired hepatic function may result in unpredictable rates of paraldehyde metabolism and so it should be administered with caution to patients with hepatic dysfunction. Close observation should be employed to detect signs of paraldehyde toxicity. Paraldehyde is contraindicated in severe hepatic insufficiency.
Use as a hypnotic or sedative should be short term only. Patients should be warned that the hypnotic effect occurs very rapidly. Paraldehyde causes drowsiness. Hence, patients receiving Paraldehyde Injection BP should not drive a motor vehicle or operate machinery.
This product contains low levels of crotonaldehyde which is known to be genotoxic and carcinogenic. Due to the content of crotonaldehyde, the recommended maximum life time dose of Paraldehyde that any individual should receive is 30 mL.

Use in pregnancy.

Use in lactation.

Interactions

Concomitant administration of paraldehyde with other CNS depressants, such as barbiturates or alcohol, should be avoided due to possible potentiation of CNS depression.
Animal studies indicate that disulfiram slows the metabolism of paraldehyde via inhibition of acetaldehyde dehydrogenase, resulting in an increase in blood concentrations of paraldehyde and acetaldehyde. Therefore, concomitant administration of paraldehyde and disulfiram should be avoided.

Adverse Effects

Intramuscular administration of Paraldehyde Injection BP is extremely painful and has produced sterile skin abscesses, sloughing of skin, fat necrosis and muscular irritation. Severe and permanent nerve damage has occurred when paraldehyde was injected intramuscularly too close to nerve trunks; care must be taken when administered by the intramuscular route.
Intravenous administration of Paraldehyde Injection BP is not recommended as it has caused pulmonary oedema, pulmonary haemorrhage, dilatation of the right side of the heart, circulatory collapse, thrombophlebitis, respiratory distress and cyanosis.
Paraldehyde Injection BP may cause skin rashes. Other side effects, such as dizziness, muscle cramps, trembling and unusual sweating, have been reported.
Toxic hepatitis and nephrosis have been reported following prolonged use of paraldehyde. Metabolic acidosis has also occurred following overdosage of Paraldehyde Injection BP and has been associated with nausea, muscular tremor, severe epigastric cramps, mental confusion, agitation, pseudoketosis, hyperacetaldehydaemia. Prolonged use may also produce tolerance and physical and/or psychological dependence on the drug.

Dosage and Administration

Paraldehyde Injection BP may be administered intramuscularly undiluted by deep injection into the buttocks taking care to avoid the vicinity of the nerve trunks. Not more than 5 mL should be administered per injection site. The usual doses are as follows.

Adults.

Hypnotic.

Sedative.

Convulsions (e.g. tetanus), convulsions from poisons, status epilepticus.

Alcohol withdrawal.

Children.

Hypnotic.

Sedative.

Convulsions (e.g. tetanus), convulsions from poisons.

Status epilepticus.

Incompatibilities.

Overdosage

Paraldehyde overdosage results in short and troubled, rapid breathing. Other characteristics include cloudy urine, decreased urination, a slow heartbeat and general weakness. This may lead to coma, severe hypotension, respiratory depression, pulmonary oedema and cardiac failure. Paraldehyde induced coma may last for several hours because it is slowly metabolised. Paraldehyde overdosage is distinguished from other CNS depressants by the odour of the drug on the breath. Metabolic acidosis with increased anion gap may also occur. Renal function may be impaired and may result in azotaemia, oliguria and albuminuria. Nephrosis, fatty changes in the kidneys or liver and/or toxic hepatitis may also occur.
Fatalities are uncommon but, when they occur, they are usually caused by respiratory failure. A few fatalities have been attributed to pulmonary oedema and right sided heart failure or metabolic acidosis.

Treatment.

Presentation

Injection (sterile, colourless or pale yellow transparent liquid), 5 mL: 5's (glass vial, AUST R 160612; Phebra product code INJ153).

Storage

Store below 25°C. Protect from light. Do not refrigerate. Use promptly after opening. Do not use if solution has a brownish colour or a sharp penetrating odour of acetic acid. Paraldehyde solidifies to form a crystalline mass at temperatures around 12°C. Warm gently if crystallised.

Poison Schedule

S4.