Prazosin shows promise in treating post-traumatic headache

Prazosin, approved in the 1970s to control hypertension and used off-label to eliminate PTSD-related nightmares, was recently shown to prevent post-traumatic headaches in veterans in a small randomized controlled trial.

The study was presented at the American Headache Society’s virtual meeting.

Prazosin is a brain-accessible alpha-1 adrenoreceptor antagonist that crosses the blood-brain barrier and reduces brain noradrenergic signaling when administered peripherally, according to researchers.

“As [Veterans Health Administration] investigators, we are committed to finding better treatments for veterans who are suffering the consequences of blast concussions, otherwise known as mild traumatic brain injuries,” Murray A. Raskind, MD, director of the Northwest Network Mental Illness Research, Education and Clinical Center in Seattle, told Healio Primary Care.

Researchers studied veterans who, every 28 days, had 8 or more days of moderate or severe headaches that lasted at least 4 hours. Veterans who had any severity or duration of headaches and received rescue medications were also included in the analysis. The patients were randomized to receive prazosin (n = 15) or placebo (n = 8) titrated over a 5-week period to a maximum dose of 5 mg mid-morning and 20 mg at bedtime. The highest dose patients could tolerate was continued for 3 months. The patients’ results at 1-month intervals were compared with baseline data.

Raskind and colleagues wrote that a “substantially greater reduction” in moderate to severe headache frequency was observed in the prazosin recipients.

These preliminary results “exceeded expectations and are highly promising,” Raskind said. “Although more placebo-controlled data need to be obtained in our ongoing trial, results to date suggest that prazosin is a reasonable and low-cost option for migraine-like post-traumatic headaches that have not responded to other treatment approaches.”