• Pethidine is used to treat pain particularly after an operation or during child birth.
  • Feeling or being sick or constipation may occur with this medicine. Your doctor may be able to prescribe medicines to take with pethidine to help with these side-effects.
  • Pethidine may make you sleepy. If this happens, do not drive or use tools or machines.
Type of medicine Opioid analgesic
Used for Pain particularly after an operation or during child birth
Also called Pamergan P100®
Available as Tablets and injection

Pethidine is used to treat moderate to severe pain. It works on the nerves and brain to reduce the pain you feel. It is particularly useful for treating pain associated with child birth and can also be used to ease pain before, during and after an operation.

Before taking pethidine make sure your doctor or pharmacist knows:

  • If you are pregnant, trying for a baby or breast-feeding.
  • If you have liver or kidney problems.
  • If you have respiratory (breathing) problems, including asthma.
  • If you have prostate or thyroid problems.
  • If you have an irregular heartbeat.
  • If you have epilepsy or hypotension (low blood pressure).
  • If you have recently had a serious head injury.
  • If you have a condition called myasthenia gravis (a muscle wasting disease).
  • If you have a condition called phaeochromocytoma (a tumour of the adrenal gland).
  • If you have been constipated for more than a week or have an inflammatory bowel problem.
  • If you have a problem with your bile duct.
  • If you are currently or have ever been dependent on drugs or alcohol.
  • If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
  • If you have ever had an allergic reaction to this or any other medicine.
  • If you have been prescribed pethidine injection, this will be given to you by your doctor or nurse, therefore the information below does not apply to you.
  • If you have been prescribed pethidine tablets, the following information does apply to you:
  • Read the manufacturer's printed information leaflet from inside the pack.
  • Take pethidine tablets exactly as your doctor has told you.
  • The usual dose of pethidine between one and three tablets. The dose should not be repeated more frequently than every four hours.
  • If you forget to take a dose, take it as soon as you remember and then continue taking your doses every four hours as before. Do not take two doses together to make up for a forgotten dose.
  • Alcohol will increase any feelings of drowsiness, so try to avoid alcoholic drinks.
  • If you are planning a trip abroad you are advised to carry a letter with you from your doctor because pethidine is a controlled drug.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Common side-effects What can I do if I experience this
Feeling or being sick Eat little and often. Stick to simple or bland foods – avoid very rich or spicy food. Your doctor may be able to prescribe a medicine to help with the sickness
Drowsiness If you do feel sleepy, do not drive or use tools or machines
Constipation Try to eat a well balanced diet containing fibre and drink 6-8 glasses of water each day. Your doctor may be able to prescribe a laxative
Dry mouth If you experience this, try sugar-free gum or sweets
Sweating Use a cold, damp flannel or sponge placed on the forehead
Difficulty passing urine, flushing of the face, a fast or fluttering heartbeat, seeing or hearing things that aren't real, mood changes, sexual problems or skin rashes If any of these occur, speak with your doctor
  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.

  • Never take more than the prescribed dose. If you suspect that you or someone else has taken an overdose of this medicine go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.
  • This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
  • If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.
  • If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
  • Never keep out of date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
  • If you have any questions about this medicine ask your pharmacist.

Further reading & references

  • British National Formulary; 62nd Edition (Sep 2011) British Medical Association and Royal Pharmaceutical Society of Great Britain, London
  • Manufacturer's PIL, Pethidine Injection; Manufacturer's PIL, Pethidine Injection, Goldshield plc, electronic Medicines Compendium. Dated April 2008.

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.

Original Author:
Helen Allen
Current Version:
Peer Reviewer:
Dr Adrian Bonsall
Last Checked:
Document ID:
3594 (v23)
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