Indications
Pethidine (also called Meperidine) is a strong opioid pain reliever used for short-term relief of moderate to severe pain, such as pain during labour, after surgery, or before and during some procedures. It is not suitable for long-term pain because of its side effects.
How It Works
Pethidine attaches to opioid receptors in the brain and spinal cord. This changes how pain signals are felt and also causes calmness and drowsiness. Its effect starts quickly and lasts about 2 to 4 hours.
Dosage and Administration
Pethidine is a controlled medicine. It is usually given as an injection into a muscle, under the skin or into a vein by a doctor or nurse in hospital. The dose depends on the patient’s age, weight, kidney function and type of pain, so it is given only as prescribed. It should be used for the shortest possible time.
Interactions
- Never use with, or within 14 days of, MAO inhibitors (such as Selegiline or Linezolid): this can cause a life-threatening reaction.
- Alcohol, Benzodiazepines, sleeping tablets, antihistamines and other opioids can cause dangerous drowsiness and slow breathing.
- Antidepressants such as Fluoxetine or Sertraline, and Tramadol, increase the risk of serotonin syndrome.
- Ritonavir, Phenytoin and Carbamazepine can change its levels and increase toxic effects.
Contraindications
- Allergy to Pethidine.
- Severe breathing problems, severe asthma attack or blocked airways.
- Use of MAO inhibitors in the last 14 days.
- Severe kidney failure, head injury with raised pressure in the skull, or bowel blockage.
Side Effects
Common effects include drowsiness, dizziness, nausea, vomiting, sweating, dry mouth, constipation and light-headedness when standing. A breakdown product called norpethidine can build up with repeated doses or kidney problems and cause shaking, muscle twitching and fits. Regular use can lead to tolerance, dependence and addiction.
Get urgent medical help for slow or shallow breathing, extreme sleepiness, fits, confusion, a very fast heartbeat with fever and agitation, or swelling of the face and difficulty breathing.
Pregnancy and Lactation
It is used during labour under medical care, but it crosses the placenta and can make the newborn sleepy and slow to breathe, so the baby is monitored. Regular use in pregnancy can cause withdrawal in the newborn. It passes into breast milk; single doses may be acceptable, but repeated doses should be avoided while breastfeeding.
Precautions and Warnings
- Use with caution in older people, and in liver, kidney, lung, thyroid or adrenal disease.
- Do not drive or use machinery after receiving it.
- It can be misused; it must be stored and given under strict control.
- Stopping after regular use should be gradual to avoid withdrawal.
Overdose
Overdose can cause very slow breathing, pinpoint pupils, deep sleep or coma, low blood pressure and fits. It is an emergency; the antidote Naloxone is given in hospital.
Therapeutic Class
Opioid analgesic (narcotic pain reliever).
Storage
Store below 30°C, protected from light, as directed on the pack. Keep in a locked place, out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.