Morphine

Brand Names

Avinza, Kadian, MS Contin, MSIR, Oramorph SR, Roxanol

What is Morphine

Morphine is a potent opiate analgesic medication which considered to be the prototypical opioid. This medicine belongs to a group of drugs called narcotic pain relievers. Morphine can usually be found in tablet form, a syrup, injection or as a suppository form.

Side effects of Morphine

• hives
• difficulty breathing
• swelling of your face, lips, tongue or throat
• shallow breathing, slow heartbeat
• seizure (convulsions)
• cold, clammy skin
• confusion
• severe weakness or dizziness
• feeling light-headed, fainting
• constipation
• warmth, tingling, or redness under your skin
• nausea, vomiting, stomach pain, diarrhea, loss of appetite
• dizziness, headache, anxiety
• memory problems
• sleep problems (insomnia)

Indication

Morphine is used for pain relief. It works by dulling the pain perception center in the brain. Short-acting formulations are taken as needed for pain. Extended-release formulations are used when around-the-clock pain relief is needed. This medicine can also be used to ease pain before, during and after operations.

Precautions

Tell your doctor if you have an allergetic reaction to any drugs or if you have:

• asthma, COPD, sleep apnea, or other breathing disorders
• liver or kidney disease
• underactive thyroid
• curvature of the spine
• a history of head injury or brain tumor
• epilepsy or other seizure disorder
• low blood pressure
• gallbladder disease
• Addison's disease or other adrenal gland disorders
• enlarged prostate, urination problems
• mental illness
• a history of drug or alcohol addiction

Dosage forms

Morphine can be given orally, rectally, by intramuscular or intravenous injection, sub-cutaneously, sublingually, or injection into the epidural or subarachnoid space. The dose for analgesia by IM injection is 100-150mcg/kg, repeated 2 hourly as required. The usual dose given at the start of surgery is 100-200mcg/kg, followed by required additional doses of 1-2mg intravenously when required. After the patient has woken up further doses of 1-2mg may be given until the patient is free of pain. Much higher doses are sometimes used during specialist surgery such as cardiac or neurosurgery.

The usual adult dose for epidural morphine is 3-7 milligrams and of subarachnoid morphine between 250mcg and 1mg. The main risk of this technique is that severe respiratory depression may occur up to 18 hours after the initial injection because of the slow circulation of cerebral spinal fluid which carries the morphine up to the brain to act on the respiratory centre.