Many very sick people take these drugs to control the pain of serious painful illness. Sometimes people stockpile morphine tablets, believing that by not taking the full prescribed dose they can acquire a lethal quantity. The problem, however, is in establishing what constitutes a lethal dose of the opioid. Knowing how many morphine tablets to accumulate and then take to bring about death is a little like asking the length of a piece of string.
Taking a single drink made up of crushed SR morphine tablets may cause death, but the result can also be unpredictable. The fast-acting liquid morphine is a more effective form of the drug, but the twin problems of sensitivity and tolerance remain. For these reasons it is difficult to recommend morphine as a stand- alone, single-dose, oral agent for a reliable death.
Morphine does, however, have a role as a supplementary or potentiating agent, (ie. a drug taken to enhance the effectiveness of another drug). While alcohol is a common potentiating agent, for people who do not drink, liquid morphine can be a good alternative. The sedation, mild euphoria and respiratory depression can often work to improve the lethal effect of many other drugs. More detail can be found in the Chapter titled ‘Drug Pre-Medication and Potentiation.