Diamorphine

Regular use during pregnancy may cause drug dependence in the foetus, leading to withdrawal symptoms in the neonate.

If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.

Administration during labour may depress respiration in the neonate and an antidote for the child should be readily available.

Administration to nursing women is not recommended as diamorphine may be secreted in breast milk and may cause respiratory depression in the infant.

Diamorphine causes drowsiness and mental clouding. If affected patients should not drive or use machines.

This medicine can impair cognitive function and can affect a patient’s ability to drive safely. This class of medicine is in the list of drugs included in regulations under 5a of the Road Traffic Act 1988. When prescribing this medicine, patients should be told:

• The medicine is likely to affect your ability to drive.
• Do not drive until you know how the medicine affects you.
• It is an offence to drive while under the influence of this medicine.
• However, you would not be committing an offence (called ‘statutory defence’) if:
  • The medicine has been prescribed to treat a medical or dental problem and
  • You have taken it according to the instructions given by the prescriber and in the information provided with the medicine and
  • It was not affecting your ability to drive safely.

Oral administration

• Hallucinations, confusion, mood changes, dysphoria and dependence.
• Headache, vertigo, dizziness and drowsiness.
• Sweating and postural hypotension.
• Miosis.
• Bradycardia, palpitations, tachycardia and facial flushing.
• Constipation, nausea, vomiting and a dry mouth.
• Ureteric or biliary spasm.
• Rashes and pruritis.
• Urinary retention.
• Decrease in libido or potency.
• Difficulty with micturition.
• Hypothermia.
• Respiratory depression and arrest.
• Circulatory depression.
• Cardiac arrest and shock.
• Syncope.
• Anorexia.
• Cramps and taste alternations.
• Insomnia.
• Weakness.

IM / IV / SC administration

The most serious hazard of therapy is respiratory.

The most common side effects are sedation, nausea and vomiting, constipation and sweating. Tolerance generally develops with long-term use, but not to constipation. Other side effects include the following:

Anaphylaxis: Anaphylactic reactions following intravenous injection have been reported rarely.

Cardiovascular: orthostatic hypotension, facial flushing, palpitations, tachycardia, bradycardia.

Central Nervous System: dizziness, vertigo, mental clouding, confusion (with large doses), hallucinations, headache, mood changes including dysphoria and euphoria.

Gastrointestinal: dry mouth, biliary spasm.

Disorders of the eye: blurred or double vision or other changes in vision, miosis.

Sexual dysfunction: long-term use may lead to a reversible decrease in libido or potency.

Skin: rash, pruritus, urticaria.

Urinary: urinary retention, difficulty with micturition, ureteric spasm, antidiuretic effect. Tolerance develops to the effects of opioids on the bladder.

Psychiatric disorders: drug dependence.

General disorders and administration site conditions: drug withdrawal syndrome.