Repetitive intravenous prochlorperazine treatment of patients with refractory chronic daily headache

OBJECTIVES: To investigate the efficacy and long-term outcome of intravenous prochlorperazine for the treatment of refractory chronic daily headache. BACKGROUND: Unlike dihydroergotamine, the treatment results of intravenous neuroleptics as first-line agents for refractory chronic daily headache have rarely been reported. METHODS: We retrospectively analyzed the data of inpatients with refractory chronic daily headache who received intravenous repetitive prochlorperazine treatment from November 1996 to March 1999. A semistructured telephone follow-up interview was done in September 1999. RESULTS: A total of 135 patients (44 men, 91 women) were recruited, including 95 (70%) with analgesic overuse. After intravenous prochlorperazine treatment, 121 (90%) achieved a 50% or greater reduction of headache intensity, including 85 (63%) who became headache-free. The mean hospital stay was 6.2 +/- 2.7 days, and mean total prochlorperazine used was 98 +/- 48 mg. Acute extrapyramidal symptoms occurred in 21 patients (16%). One hundred twenty-four patients (92%) were successfully followed up, with a mean duration of 14.3 +/- 7.5 months. Compared with pretreatment status, 93 patients (75%) considered their headache intensity decreased, and 86 patients (69%) considered their headache frequency decreased, although 40 (32%) still had a daily headache. Of the 87 patients with analgesic overuse who could be followed, 61 (70%) no longer overused analgesics. Poor response to prochlorperazine treatment (relative risk, 1.8) and presence of major depression (relative risk, 1.8) were predictors of persistent chronic daily headache at follow-up. CONCLUSIONS: Prochlorperazine was effective and safe in the treatment of patients with refractory chronic daily headache with or without analgesic overuse. Compared with dihydroergotamine, prochlorperazine seemed less effective at achieving "freedom from headache" during hospitalization, but had a similar outcome at follow-up.