MedWire News: People who suffer from migraines or cluster headaches may benefit from oxygen therapy to provide short-term symptom relief, say researchers.

However, the team found no evidence to suggest that oxygen therapy reduces the frequency of migraines or cluster headaches.

A number of drug therapies are available for the prevention and treatment of migraine and cluster headaches. However, some doctors also prescribe oxygen therapy for their headache patients, explain Dr Michael Bennett, from the Prince of Wales Hospital in Randwick, New South Wales, Australia, and team.

To investigate whether oxygen therapy is a useful treatment for such patients, the researchers reviewed the results of nine published studies that assessed the effectiveness of normobaric and hyperbaric oxygen therapy in 201 participants with migraines and cluster headaches.

Normobaric oxygen therapy involves patients inhaling pure oxygen through a mask at normal room pressure, while hyperbaric oxygen therapy involves patients breathing oxygen at high pressure in a specially designed chamber.

Analysis of the pooled data revealed that migraine patients assigned to hyperbaric oxygen therapy were more than five times more likely to report pain relief than those assigned to a dummy treatment.

However, hyperbaric oxygen therapy did not appear to prevent migraine episodes, or reduce the incidence of vomiting and nausea or the need for rescue medications.

The team also found that cluster headache patients were more than seven times more likely to report pain relief after receiving normobaric oxygen therapy, compared with those whom received a dummy treatment. However, this finding was based on the results of just one study.

None of the studies investigated assessed whether normobaric oxygen therapy was effective in migraine patients.

Dr Bennett and team conclude: "There was some evidence that hyperbaric oxygen therapy was effective for the termination of acute migraine... and weak evidence that normobaric oxygen therapy was similarly effective in cluster headache."

They continue: "We believe that hyperbaric oxygen is... a reasonable measure for migraineurs who have not responded to other measures to treat an acute attack."

But the researchers add: "Poor availability of hyperbaric chambers makes this an option only in a minority of health facilities. Most physicians treating headaches will continue to rely on established and emerging pharmacological options for treating and preventing acute attacks."

The research is published in the Cochrane Database of Systematic Reviews.