Oral treatment allows independence and can be provided at home where most patients will prefer to die.
• A simple aqueous solution23 may be used initially, the strength being adjusted to give a volume of 5-10 ml per dose, e.g. begin with 1 or 2 mg/ml.
• Alternatively, sustained-release tablets (MST Continus, Oramorph SR) may be preferred.
• The usual oral starting dose to replace a weaker analgesic, e.g. co-proxamol, is 2.5-10 mg 4-hourly (2.5 mg in the frail elderly) of the aqueous solution or 10-30 mg 12-hourly of the sustained-release formulations. Alternatively, use suppositories or buccal (sublingual) formulations (the latter route bypasses the presystemic elimination and does not require such high doses as when swallowed).
• Dose and frequency should be adjusted to meet the patient's need. The interval of sustained-release tablets should remain unaltered, i.e. 12-hourly.
• Breakthrough pain when the patient is taking a sustained-release preparation may be controlled by an additional dose of the aqueous solution; it gives the patient confidence.
• Change to morphine from other high-efficacy opioids; higher starting doses of oral morphine will be needed.
• A larger dose at night (1.5-2 x daytime dose) or an added hypnotic may allow the patient to pass the night without waking in pain (and so to omit one night dose).
• Constipation will occur, see below; it is essential to manage it.
• Initial drowsiness (a few days) and confusion (in the elderly) are common and usually pass off.
• Initial nausea and vomiting are common: an antiemetic, e.g. prochlorperazine, controls it and can generally be withdrawn after 4-5 days.
• Respiratory depression is seldom a problem with morphine dose escalated in this way.
• Dependence need not be feared. Both physical and psychological dependence occurs, but the latter to only a small degree compared with drug abuse or other chronic pain syndromes. The
23 Solutions of morphine deteriorate once they are exposed to air, and if exposed to light (keep in dark) and heat, they lose potency over as few as 2-4 weeks; competent pharmaceutical advice and preparation is required; stable formulations have been developed (Oramorph). The taste of morphine is bitter and patients may choose an accompanying drink to mask it. Tablets may be used.
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Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.