Consumer medicine information

PENTOTHAL™ For Injection

thiopental sodium

Consumer Medicine Information

What is in this leaflet

This leaflet answers some common questions about Pentothal for Injection.

It does not contain all the available information. 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 taking Pentothal for Injection against the benefits they expect it will have for you.

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

Keep this leaflet. You may need to read it again.

What Pentothal for Injection is used for

Pentothal for Injection is used as a general anaesthetic, or to make you sleepy before using another anaesthetic agent, or to control seizures.

This medicine belongs to a group of medicines called barbiturates.

This medicine works as a short acting depressant of the nervous system, which is composed of the brain and spinal cord. It creates a sleep like state and loss of consciousness to prevent pain and discomfort during surgery.

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.

Thiopental is addictive.

Before you are given Pentothal for Injection

When you must not be given it

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

  • any other barbiturates
  • any medicine containing thiopental sodium
  • 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

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

You should not be given Pentothal for Injection if you have:

  • porphyria
  • a swollen jaw, mouth or neck

Before you are given it

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:

  • low blood pressure
  • liver or kidney disease
  • heart problems

Tell your doctor if you are pregnant or plan to become pregnant or are breast-feeding. Your doctor can discuss with you the risks and benefits involved.

If you have not told your doctor about any of the above, tell him/her before you start taking Pentothal for Injection.

Taking other medicines

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

Some medicines and Pentothal for Injection may interfere with each other. These include:

  • medicines used to treat gout, such as probenacid
  • medicines used to widen blood vessels and decrease in blood pressure, such as diazoxide
  • medicines to relieve breathing problems, such as aminophylline
  • ethanol (alcohol)
  • medicines used as sedatives or to treat anxiety, such as benzodiazepines
  • medicines used to depress the nervous system which is composed of the brain and spinal cord
  • medicines used to treat pain relief, such as opioids analgesics
  • medicines used to help the kidneys get rid of salt and water by increasing the amount of urine produced, such as diuretics
  • ketamine, an anaesthetic
  • magnesium sulfate
  • medicines used to treat mental illness or psychotic conditions and to relieve severe nausea and vomiting, such as phenothiazine
  • iodine for thyroid problems

These medicines may be affected by Pentothal for 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 taking this medicine.

How to take Pentothal for Injection

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

How much is given

Your doctor will decide how much you will receive. The dosage will depend on your condition and other factors such as weight, sex and age.

How it is given

Thiopental is given by intravenous injection.

If you are given too much (overdose)

As Pentothal for Injection is given to you under the supervision of your doctor, it is very unlikely that you will receive too much. However, if you experience any severe side effects after being given Pentothal for Injection, tell your doctor immediately or go to Accident and Emergency at the nearest hospital. You may need urgent medical attention.

In case of overdose, immediately contact the Poisons Information Centre for advice (telephone 13 11 26).

Symptoms of Pentothal for Injection overdose include the side effects listed below in the ‘Side Effects’ section, but are usually of a more severe nature.

While you are being given Pentothal for 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 Pentothal for Injection.

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

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

If you are about to have any blood tests, tell your doctor that you have been given this medicine. It may interfere with the results of some tests.

Keep all of your doctor’s appointments so that your progress can be checked.

Things to be careful of

Be careful driving or operating machinery until you know how Pentothal for Injection affects you. This medicine may affect alertness and tasks requiring co-ordination in some people. If you have any of these symptoms, do not drive, operate machinery or do anything else that could be dangerous.

Be careful when drinking alcohol while you are being given this medicine. If you drink alcohol, impairment of motor skills may be worse.

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 bed or 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.

Some self help measures suggested below may help your condition. Your doctor or pharmacist can give you more information about these measures.

Side effects

Tell your doctor or pharmacist as soon as possible if you do not feel well after you have been given Pentothal for Injection. This medicine helps most people, 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 or pharmacist to answer any questions you may have.

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

  • involuntary muscle movements
  • coughing
  • hiccups
  • sneezing
  • shivering

Tell your doctor as soon as possible if you notice any of the following:

  • allergic reactions, including sudden life-threatening allergic reactions
  • itchy rash
  • shallow breathing
  • changes in heart rate (fast, slow or irregular)
  • prolonged sleepiness or recovery
  • low blood pressure
  • difficulty in breathing

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

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

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

After using Pentothal for Injection


Pentothal for Injection will be stored in the pharmacy or on the ward. The injection should be stored below 25°C.

Product description

What it looks like

Pentothal for Injection is a yellowish powder available as 500 mg vials in packs of 25 and 50*.

*not all pack sizes are marketed.


Pentothal for Injection contains 500 mg of thiopental sodium as the active ingredient.

Pentothal for Injection also contains the following inactive ingredient:

  • anhydrous sodium carbonate

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


Pentothal for Injection is supplied by:

Australian Sponsor:
Link Medical Products Pty Ltd
5 Apollo Street
NSW 2102

Pentothal for Injection is available in the following strengths:
500 mg powder for injection vial
AUST R 73505

This leaflet was updated in December 2020.

Published by MIMS February 2021