The absorption of
mexiletine is reduced in patients following a myocardial infarction, and very markedly reduced and delayed if
opioids (diamorphine or morphine) are given concurrently.
The delay and reduction in the absorption would seem to limit the value of oral
mexiletine during the first few hours after a myocardial infarction, particularly if opioid analgesics are used. The manufacturer suggests that a higher loading dose of oral
mexiletine may be preferable in this situation. Alternatively, an
intravenous dose of
mexiletine may be given.