Delayed absorption of many (paracetamol, aspirin, other NSAIDs and zolmitriptan) but not all (sumatriptan, rizatriptan) drugs during migraine attacks and most likely normal gastric emptying outside attacks. A review

Background In most pharmacokinetic studies, the oral absorption of drugs is impaired during migraine attacks but exceptions occur. A study on gastric emptying using gastric scintigraphy indicated that gastric stasis also occurs interictally in migraine. These studies were reviewed critically. Results In seven studies, mainly investigating NSAIDs and analgesics, the early absorption of the drugs during 112 migraine attacks was delayed. The absorption of sumatriptan is usual in therapeutic doses, and rizatriptan was normal during 131 migraine attacks. The interictal gastric stasis observed using gastric emptying scintigraphy (GES) with solids (n=13) could not be confirmed in a larger study (n=27) using the same method. Also gastric emptying measured with GES with liquids (n=7) and epigastric impedance (n=64) was normal outside migraine attacks. Conclusions and possible clinical implications Drug absorption is not generally impaired during migraine attacks. Gastric emptying is most likely normal in the majority of migraine patients outside attacks. Prokinetic and antiemetic drugs such as metoclopramide and domperidone should not be routinely combined with oral analgesics or oral triptans. If, however, nausea is severe or vomiting occurs, treatment with an antiemetic with proven efficacy on the nausea of migraine can be indicated.