The effect of metoclopramide on the absorption of effervescent aspirin in migraine.

1 The absorption of effervescent aspirin was studied in two groups of patients during attacks of migraine. The first group received effervescent aspirin alone whilst the second group received intramuscular metoclopramide before effervescent aspirin. 2 After effervescent aspirin alone there was significant impairment in the rate of aspirin absorption during migraine attacks compared with the rate of aspirin absorption in normal volunteers and in the same patients when headache-free. 3 When metoclopramide was given before effervescent aspirin the rate of aspirin absorption during migraine attacks was not significantly different from that obtained in normal volunteers given effervescent aspirin alone or from that obtained in the patients themselves when given both metoclopramide and effervescent aspirin when headache-free. 4 It is concluded that the impairment of absorption of effervescent aspirin during migraine attacks is related to impaired gastro-intestinal motility with delayed gastric emptying and that this impaired motility can be overcome by parenteral metoclopramide.