Over-the-counter painkillers, such as aspirin and ibuprofen, can reduce the risk of Parkinson's disease, US researchers reported.
They found that regular users of such drugs, which ease the pain of arthritis and headaches, were much less likely to have Parkinson's than non-users or sporadic users.
The drugs, known as non-steroidal anti-inflammatory drugs or NSAIDS, are taken daily by millions of people.
A team from University of California Los Angeles studied 579 men and women from California, half of whom had Parkinson's disease. They were asked if they had taken aspirin or other NSAIDs such as ibuprofen once a week or more at any point in their life for at least a month.
Those who took two or more pills a week for at least one month were considered regular users.
Acetaminophen, also known as paracetamol, is not an NSAID and does not act in the same way as aspirin, ibuprofen, naproxen and similar drugs.
NSAID users are protected against Parkinson's
The researchers found the NSAID users were less likely to have Parkinson's, especially those using ibuprofen or other non-aspirin NSAIDs.
"Our findings suggest NSAIDs are protective against Parkinson's disease, with a particularly strong protective effect among regular users of non-aspirin NSAIDs, especially those who reported two or more years of use," UCLA's Angelika Wahner, who worked on the study, said.
"Given these results and the growing burden of Parkinson's disease as people age, there's a pressing need for further studies explaining why these drugs may play a protective role," she added.
Aspirin works best on women
Women who took aspirin regularly lowered their risk of Parkinson's disease by nearly 40 percent, Wahner and colleagues reported in the journal Neurology.
"Interestingly, aspirin only benefited women. It may be that men are taking lower doses of aspirin for heart problems, while women may be using higher doses for arthritis or headache," Wahner said.
Epidemiologist Beate Ritz, who also worked on the study, said the drugs may prevent damaging inflammation in the brain.
"It's possible the anti-inflammatory agent in NSAIDs may contribute to the observed protective effect of the drugs, but the exact mechanism isn't clear and further research is needed," Ritz said.
Parkinson's disease, which affects more than a million patients in the United States alone, is marked by the death of brain cells that produce dopamine.
Dopamine is a neurotransmitter, or message-carrying chemical, associated with movement. Drugs can delay symptoms for a while, but there is no cure. –(Reuters)
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