Another difficulty with opioids is the rapid development of tolerance when the drugs are taken for any period of time. Within days, the dose of the drug that initially had a powerful analgesic effect in controlling the person’s pain can become almost ineffective.
To obtain the same pain relief the dose must be increased. If these drugs are taken over a long period, very large doses might be needed to provide adequate pain control. These required doses can easily become so large that if they had been taken before the person’s tolerance was developed, death could well have been the result.
It is this development of tolerance, and its rapid loss once the drugs stop, that often leads to the accidental death of people who self-administer opiates (especially illegal, recreational opioids such as heroin). If there is a break in supply and the acquired tolerance is lost, a sudden resumption may result in an unexpected fatal overdose. This is a common occurrence when heroin users are jailed for some reason and deprived of their supply. Their tolerance is lost and their sensitivity is increased. If their ‘habit’ is resumed on release, an overdose death can often result.
The Opioid Antidote
Another important consideration when thinking of using opioids to end life, is the ready availability of the fast-acting and effective antidote, naloxone. Naloxone competes with the opioids for the receptors in the brain, displacing any of the opioids that are present. Naloxone can rapidly reverse the effects of the drug. People who are close to death from respiratory failure (brought about by a lethal dose of opioid) can be rapidly resuscitated when naloxone is administered by injection or even by nasal spray.
