diamorphine hydrochloride at a glance
Medicine class
Strong opioid analgesic
Licensed roles
Severe pain and breathlessness in acute pulmonary oedema
Administration
Powder prepared for intravenous, intramuscular or subcutaneous injection
Important risks
Drowsiness, respiratory depression, constipation, dependence and withdrawal
What is diamorphine hydrochloride used for?
The selected product is licensed for:
Severe pain associated with surgery
Severe pain associated with myocardial infarction
Pain in terminal illness
Breathlessness in acute pulmonary oedema
Diamorphine is also sometimes used for pain relief during labour, although this is not a licensed indication of the selected product.
How does diamorphine hydrochloride work?
Diamorphine enters the brain rapidly and is converted to monoacetylmorphine and then morphine. These active opioids reduce pain signalling and the emotional response to pain, but can also depress breathing and alertness.
diamorphine hydrochloride preparations and strengths
Injection
Route: Parenteral
Strengths: 5 mg, 10 mg, 30 mg, 100 mg
How to take diamorphine hydrochloride
A healthcare professional reconstitutes this sterile powder and injects it under the skin, into a muscle or into a vein as prescribed. The prepared solution should be used immediately. Do not drink alcohol or drive or operate machinery if drowsy, confused or otherwise impaired.
Never share it with anyone.
Tell the healthcare team about all medicines, alcohol use, and breathing, kidney, liver or bowel problems.
Do not stop ongoing treatment suddenly without an agreed withdrawal plan.
diamorphine hydrochloride side effects
Common or expected effects
- Drowsiness or sedation
- Feeling or being sick
- Constipation
- Sweating
- Dizziness or confusion
- Itching or rash
- Dry mouth
- Difficulty passing urine
Get urgent medical advice
- Slow, shallow or difficult breathing
- Severe drowsiness, reduced consciousness or coma
- Severe allergic reaction with swelling, breathing difficulty or collapse
- Marked low blood pressure or fainting
- Dependence, addiction or significant withdrawal symptoms
- Seizures or severe confusion
diamorphine hydrochloride in pregnancy
Use during pregnancy requires an individual benefit–risk assessment, usually involving maternity or specialist care. Regular exposure can cause neonatal withdrawal; use near delivery can depress the baby’s breathing and may affect the first feed.
diamorphine hydrochloride while breastfeeding
The selected product information does not recommend use while breastfeeding because diamorphine can enter milk and may depress the infant’s breathing. NHS SPS advises that cautious specialist use may sometimes be possible for full-term healthy infants with monitoring, although morphine is preferred. Seek specialist advice.
diamorphine hydrochloride interactions
Other substances can alter diamorphine’s sedative, respiratory and gastrointestinal effects. Tell the prescriber about prescribed, non-prescription and recreational substances.
Alcohol
Can increase sedation, low blood pressure and serious opioid effects.
Benzodiazepines, sleeping tablets, anxiolytics and other CNS depressants
May increase or prolong sedation and respiratory depression.
Gabapentin and pregabalin
Combined use can cause profound sedation, respiratory depression, low blood pressure, coma or death.
Common questions about diamorphine hydrochloride
Answers are fully visible for fast scanning and source review.
Is diamorphine hydrochloride the same substance as heroin?
Diamorphine is pharmaceutical diacetylmorphine, the opioid also known as heroin. Prescribed diamorphine is manufactured, supplied and administered as a tightly controlled medicinal product.
Why is it used instead of morphine?
Diamorphine enters the brain and begins acting more rapidly than morphine. Choice depends on the indication, route, clinical setting and individual risks.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.