What potential side effect can result from high dose opioid therapy?

High dose opioid therapy can lead to a number of adverse effects, one of which is myoclonus due to increased levels of metabolites. Opioids are metabolized in the liver, and some metabolites can have neuroexcitatory effects. At high doses, the accumulation of these metabolites increases the likelihood of experiencing myoclonus, which is characterized by involuntary muscle jerks. This side effect is particularly notable with certain opioids, such as morphine and meperidine, which are known for producing this outcome when dosages are elevated.

In contrast, although severe respiratory depression is a well-recognized and serious risk associated with high doses of opioids, the specific link to myoclonus highlights the neurological implications of metabolite accumulation. Increased appetite and weight gain are generally not associated with opioid use; rather, opioid therapy may lead to gastrointestinal disturbances. Sleep disturbances can occur as well, but the focus here on myoclonus emphasizes the unique potential neurophysiological responses that arise from elevated metabolite levels during high dose opioid therapy.