A new method of scanning the brains of Alzheimer's patients has provided clear evidence that popular painkillers may be able to help.
Scans revealed the extent of Alzheimer's plaques
It may also help doctors diagnose the approach of Alzheimer's long before any symptoms are experienced.
Scientists at the University of California at Los Angeles (UCLA) are now hopeful of two major breakthroughs - not only the ability to detect Alzheimer's before significant brain damage has happened, but the ability to treat these patients once they are discovered.
The UCLA team has developed a chemical which sticks to the characteristic "plaques" which form in the brain tissue of patients with Alzheimer's disease.
The chemical, called FDDNP, binds to the plaques in the brain, and can be picked up on a PET brain scan.
It allows doctors to test far more easily whether treatments are having an effect.
The first success, published in the journal Neuroscience, was to clearly demonstrate that the painkillers could have an effect on the amyloid plaques in Alzheimer's brain tissue.
Over-the-counter medications such as ibuprofen appeared to dissolve away the protein clumps believed by many to be responsible for dementia symptoms.
One of the researchers, Dr John Breitner, said: "These studies suggest a previously unsuspected way in which the drugs may interact with Alzheimer myeloid.
"They show that different drugs in this class may have different effects on amyloid."
Dr Gary Small, the co-author of the report, added: "This new technology will likely help us monitor new vaccines and drugs designed to prevent and treat the brain damage caused by Alzheimer's disease."
The same research group has already discovered that injecting FDDNP into the brain actually highlights small amyloid plaques, even though the volunteers had no external sign of dementia.
Picking the patients
The researchers are hopeful that it will be possible in future to determine which patients are likely to go on and develop Alzheimer's disease on the basis of brain scans.
Such people could then hopefully be given preventive treatment - perhaps even based on the ability of the painkillers to dissolve the plaques.
Researcher Professor Jorge Barrio said: "We believe that this observation is very important because the early diagnosis of Alzheimer's disease now has an underlying purpose - early therapeutic intervention at the stage where brain cell degeneration is minimal.
"This would provide hope to patients and families by modifying outcomes."
Professor Tonmoy Sharma, director of the Centre for Neuroscience Research, said that the research was "interesting".
"There are a number of studies under way into the effects of these drugs in people with Alzheimer's, so we must now await the results of these.
"What this shows is a possible biochemical basis to the theory that these painkillers may help."