Chronic paroxysmal hemicrania and hemicrania continua. Interval between indomethacin administration and response.

The interval between indomethacin dosage and clinical response was assessed in hemicrania continua (n = 12) and chronic paroxysmal hemicrania (n = 11) sufferers. The number of trials per patient ranged from 1 to 30. At the time of testing, the patients had "considerable" pain after discontinuation of the drug. The dosage used was the usual one for that patient at the given pain level; ie, 25 or 50 mg tid. All the patients had a complete, long-term response to treatment. Nevertheless, the average interval between drug intake and pain relief during the present study ranged between 30 minutes and 48 hours in both disorders. In most patients (10 in both groups), the indomethacin effect was complete within 24 hours, and frequently within 8 hours. It is suggested that interindividual differences in dosage and timing to abolish the headaches may be due to different bioavailability or individual sensitivity. Recommendations on indomethacin testing in unilateral headaches are given.