High-dose aspirin reduces pain for severe headache and migraine

An inexpensive, hundred-year-old therapy for pain - aspirin - is effective in high doses for the treatment of severe headache and migraine caused by drug withdrawal, according to a new study by researchers with the UCSF Headache Centre. Study participants were administered aspirin through an IV and 25 percent of the time they reported a significant reduction in pain - three points on the 10-point pain scale. (A difference of three points downgrades a headache from severe to moderate, moderate to mild, or from mild to pain-free). Participants reported a more modest pain reduction about 40 percent of the time.

The findings are noteworthy because high-dose intravenous aspirin is not widely available for headache sufferers in the United States, the authors say. Aspirin also is nontoxic, non-addictive, non-sedating, has few side effects for adults, and is less expensive than drug regimens such as triptans that physicians typically prescribe to headache patients to combat severe pain.

The study was published in the September 21, 2010, issue of Neurology, the medical journal of the American Academy of Neurology.

'These results tell migraine sufferers, their doctors and insurance providers that high-dose intravenous aspirin is a beneficial way to treat difficult withdrawal headaches via a medicine that is not addictive or toxic,' said Peter Goadsby, MD, PhD, lead investigator of the study, professor and director of the UCSF Headache Centre. 'We hope to make this inexpensive therapy more available to patients seeking treatment for severe pain.'

Many headache and migraine sufferers can manage pain without hospital stays. However, for severe pain that is difficult to manage, medication overuse often is a complicating factor. To develop a successful treatment plan for these patients, physicians first turn to a hospital inpatient program where medication withdrawal can be overseen by a neurologist or pain specialist. High-dose intravenous aspirin can help patients manage headache pain while undergoing medication withdrawal, the study shows.

The American Academy of Neurology estimates that more than 30 million Americans suffer from migraine, a syndrome characterised by recurrent, often excruciating headaches. The National Headache Foundation estimates that migraine causes 157 million lost workdays each year due to pain and associated migraine symptoms, resulting in a $13 billion burden on American employers.

Further research is needed to understand how exactly the aspirin works to reduce headache pain, the UCSF team said, but the findings give neurologists a safe and effective treatment option for migraine sufferers that is less expensive than the alternative multi-drug alternative. At present, the cost for IV aspirin costs around $7 per dose depending on the drug provider. Triptans cost about $22 per pill.

For the study, researchers reviewed the charts of 168 patients ranging in age from 18 to 75 years - 51 were men and 117 were women. Nearly all subjects (159) were admitted to the hospital for severe headache complicated by medication overuse. Participants received doses of one gram of aspirin - the equivalent of three times the dose for typical pain relief - through an IV, and averaged five doses.

Nurses' notes and the hourly diaries of 86 participants were used to measure the safety and effectiveness of the high-dose intravenous aspirin. Participants kept hourly diaries about their pain before, during and after treatment, rating their pain on a 10-point scale. Scores of 1-3 associate with a mild headache, 4-7 indicates a moderate headache, and 8-10 signifies a severe headache.

Approximately six percent of participants experienced side effects ranging from nausea and vomiting to pain from the IV insertion, but none were considered severe. Potential side effects of aspirin include heartburn, nausea, bleeding, worsening of asthma, rash and kidney impairment.

'It is important to acknowledge that a placebo was not used in this case because participants knew they were receiving aspirin therapy,' Goadsby said. 'However, a number of previous placebo-controlled trials have shown intravenous aspirin to be effective for migraine.'