morphine
Brand names MST Continus, MXL, Oramorph, Sevredol
Used in the following combined preparations Cyclimorph, Omnopon
GENERAL INFORMATION
In use since the 19th century, morphine belongs to a group of drugs called the opioid analgesics . These drugs are derived from opium, which is obtained from the unripe seed capsules of the opium poppy.
Morphine is used to relieve the severe pain that can be caused by heart attack, injury, surgery, or chronic diseases such as cancer. It is also sometimes given as a premedication before surgery.
The painkilling effect of morphine wears off quickly, in contrast to some other opioid analgesics, and it may be given in a special slow-release (long-acting) form to relieve continuous severe pain.
This drug is habit-forming, and dependence and addiction can occur. However, most patients who take it for pain relief over brief periods of time do not become dependent and are able to stop taking it without difficulty.
QUICK REFERENCE
Drug group Opioid analgesic.
Overdose danger rating High
Dependence rating High
Prescription needed Yes
Available as generic Yes
INFORMATION FOR USERS
Your drug prescription is tailored for you. Do not alter your dosage without checking with your doctor.
How taken
Tablets, SR-tablets, capsules, SR-capsules, liquid, SR-granules, injection, suppositories.
Frequency and timing of doses
Every 4 hours; every 12-24 hours (SR- preparations).
Adult dosage range
5-25mg per dose; however, some patients may need 75mg or more per dose. Doses vary considerably for each individual.
Onset of effect
Within 1 hour; within 4 hours (SR- preparations).
Duration of action
4 hours; up to 24 hours (SR-tablets).
Diet advice
None.
Storage
Keep in a closed container in a cool, dry place out of the reach of children.
Missed dose
Take as soon as you remember. Return to your normal dosing schedule as soon as possible.
Stopping the drug
If the reason for taking the drug no longer exists, you may stop the drug and notify your doctor.
OVERDOSE ACTION
Seek immediate medical advice in all cases. Take emergency action if symptoms such as slow or irregular breathing, severe drowsiness, or loss of consciousness occur.
POSSIBLE ADVERSE EFFECTS
Nausea, vomiting, and constipation are common, especially with high doses.
Anti-nausea drugs or laxatives may be needed to counteract these symptoms.
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Symptom/effect
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Frequency
Common
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Rare
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Discuss doctor
Only if severe
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with
In all cases
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Stop taking drug now
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Call
doctor
now
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Drowsiness
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Nausea/vomiting
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S
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Constipation
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Dizziness
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Confusion
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Breathing difficulties
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1
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INTERACTIONS
Sedatives
Morphine increases the sedative effects of other sedating drugs including antidepressants, antipsychotics, sleeping drugs, and antihistamines.
Monoamine oxidase inhibitors (MAOIs)
These drugs may produce a severe rise in blood pressure when taken with morphine.
SPECIAL PRECAUTIONS
Be sure to tell your doctor if:
▼ You have long-term liver or kidney problems.
You have heart or circulatory problems.
▼ You have a lung disorder such as asthma or bronchitis.
You have thyroid disease.
You have a history of epileptic fits.
You are taking other medications.
Pregnancy
▼ Not usually prescribed. May cause breathing difficulties in the newborn baby. Discuss with your doctor.
Breast-feeding
The drug passes into the breast milk, but at low doses adverse effects in the baby are unlikely. Discuss with your doctor.
Infants and children
Reduced dose necessary.
Over 60
▼ Increased likelihood of adverse effects. Reduced dose may therefore be necessary.
Driving and hazardous work
People on morphine treatment are unlikely to be well enough to undertake such activities.
Alcohol
▼ Avoid. Alcohol may increase the sedative effects of this drug.
PROLONGED USE
The effects of the drug usually become weaker during prolonged use as the body adapts. Dependence may occur if the drug is taken for extended periods.
