Optimal Routes of Administration of Ergotamine Tartrate in Cluster Headache Patients. A Pharmacokinetic Study*

Abstract
Bioavailability and rate of absorption of ergotamine were studied in eight cluster headache patients outside attacks. In a cross-over design, approximately 2 mg ergotamine tartrate was administered as effervescent tablets, suppositories, and from an inhalation device, with 0.25 mg intravenously as the reference. Ergotamine in plasma was measured by high performance liquid chromatography with fluorescence detection from 5 to 420 min. For all three routes of administration, a similar low (0.5–4.2%) bioavailability of ergotamine was estimated. Only inhalation of ergotamine resulted in early (at 5 min) peak concentrations of ergotamine in plasma and is therefore most likely to relieve the short-lived attacks of cluster headache. The inhalation route for ergotamine poses problems, however, and we suggest ways of improving the inhalation device.