Indications
Morphine Sulfate is a strong opioid painkiller used to relieve moderate to severe pain that is not controlled by weaker painkillers, such as pain after surgery or injury, cancer pain and pain in serious illness. It may also be used to ease breathlessness in palliative care. Immediate-release forms act quickly; modified-release (retard) forms give steady relief over 12 or 24 hours.
How It Works
Morphine attaches to opioid receptors in the brain and spinal cord. This blocks pain signals and changes how the brain feels pain, providing strong pain relief. It also causes drowsiness and slows breathing and gut movement.
Dosage and Administration
Take exactly as prescribed. The dose is individual and is adjusted by the doctor according to pain, response and side effects. Modified-release tablets must be swallowed whole, not crushed, chewed or broken, because this can release a dangerous dose all at once. Injections are given by a doctor or nurse. Do not stop suddenly after regular use; the doctor will reduce the dose gradually. A laxative is usually needed while taking it.
Interactions
Alcohol, Benzodiazepines such as Diazepam, sleeping tablets, Gabapentin, Pregabalin, sedating antihistamines, antipsychotics and other opioids can cause severe drowsiness, breathing problems, coma or death when combined. MAO inhibitors must not be used with it or within 14 days. Rifampicin may reduce its effect. Medicines with anticholinergic effects increase constipation and urine retention.
Contraindications
Do not use with severe breathing problems or slowed breathing, acute or severe asthma, blocked bowel (paralytic ileus), acute alcohol intoxication, head injury or raised pressure in the skull, during or within 14 days of MAO inhibitors, or if allergic to morphine.
Side Effects
Common effects include constipation, nausea, vomiting, drowsiness, dizziness, confusion, dry mouth, sweating, itching and difficulty passing urine. Long-term use can lead to tolerance, physical dependence and addiction, and low sex hormone levels.
Get urgent medical help if breathing becomes slow or shallow, you are very sleepy or hard to wake, have pinpoint pupils, blue lips, severe confusion, fainting, a slow heartbeat, or signs of a severe allergic reaction. Family members should know these warning signs.
Pregnancy and Lactation
Use in pregnancy only if clearly needed and prescribed. Regular use late in pregnancy can cause withdrawal symptoms and breathing problems in the newborn. Morphine passes into breast milk and may cause drowsiness or breathing problems in the baby; breastfeeding is not recommended during regular use unless the doctor advises.
Precautions and Warnings
Morphine is a controlled medicine with a risk of misuse and addiction; keep it locked away and never share it. Use with care in older people and in kidney, liver, lung, thyroid, adrenal or prostate disease, low blood pressure, or a history of substance misuse. Do not drive or operate machinery if drowsy. Avoid alcohol.
Overdose
Overdose causes extreme sleepiness, pinpoint pupils, very slow or stopped breathing, cold clammy skin, low blood pressure and can be fatal. Call emergency services immediately. Naloxone, given by health professionals, can reverse the effects.
Therapeutic Class
Opioid analgesic (controlled drug)
Storage
Store below 30°C in a dry place, away from light, in a locked place out of the sight and reach of children. Return unused medicine to a pharmacy for safe disposal.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.