A PAINKILLER taken by millions of Britons may offer protection against Parkinson's and even slow progress of the disease, a study suggests.
Researchers in the US showed that ibuprofen lowered the risk of developing Parkinson's disease by as much as 38 per cent.
But other pain-relieving medicines, such as aspirin, naproxen and diclofenac, did not have the same effect.
Researchers believe ibuprofen may have a unique ability to protect the brain cells that are lost by Parkinson's patients.
If so, it is possible the drug may help to hold back the progressive disease.
But experts yesterday warned that excessive use of ibuprofen can lead to harmful side-effects, such as gastrointestinal bleeding, meaning patients should not rush to start taking the drug to prevent Parkinson's without further research.
The scientists, from the Harvard School of Public Health, analysed data from more than 37,000 male health professionals and almost 99,000 female nurses.
Over a six-year period, 156 men and 135 women were diagnosed with Parkinson's disease. Their use of pain-relieving medicines known as non-steroidal anti-inflammatory drugs (NSAIDS) was recorded, along with other information such as age, smoking habits and diet.
The results, published in the journal Neurology, showed that those who took ibuprofen two or more times a week were 38 per cent less likely to develop Parkinson's than those who did not.
A follow-up analysis combining data from other studies of NSAIDS use indicated a 27 per cent reduced risk associated with ibuprofen.
Senior author Alberto Ascherio said: "There is no cure for Parkinson's disease, so the possibility that ibuprofen, an existing and relatively non-toxic drug, could help protect against the disease is captivating."
Lead researcher Xiang Gao added: "Because the loss of brain cells that leads to Parkinson's disease occurs over a decade or more, a possible explanation of our findings is that use of ibuprofen protects these cells. If so, use of ibuprofen could help slow the disease's progression."
Dr Kieran Breen, director of research at Parkinson's UK, said: "We know that inflammatory changes in the brain may be involved in the death of nerve cells which cause Parkinson's, particularly in the early stages of the condition.
"It's difficult to know exactly what effect ibuprofen may be having on the death of nerve cells in the brain, and how it might affect whether somebody will get Parkinson's. But there would seem from this study to be an interesting link.
"However, there is no evidence that taking ibuprofen slows the rate of progression of the condition. We would not recommend that people rush to take it, as ibuprofen has many other effects that may be harmful if taken over a long period."