Dementia is a growing health problem around the world, and right now there are no safe or affordable treatments that can slow it down.
Researchers in Canada are testing whether a well-known cough medicine, Ambroxol, could help people with dementia linked to Parkinson’s disease.
The study was led by Dr. Stephen Pasternak at the Lawson Research Institute, which is part of St. Joseph’s Health Care London. His team wanted to see if Ambroxol, a drug used safely in Europe for many years to treat breathing problems, could protect the brain and help memory in people with Parkinson’s disease dementia (PDD).
This type of dementia causes memory loss, confusion, hallucinations, and changes in mood. It affects about half of Parkinson’s patients within ten years of diagnosis.
The researchers ran a 12-month clinical trial with 55 people who had Parkinson’s disease and dementia. Half of the group took Ambroxol every day, while the other half got a placebo—a pill with no active drug.
The team tracked changes in memory, psychiatric symptoms like anxiety or depression, and a blood marker called GFAP, which is linked to brain cell damage.
The results, published in JAMA Neurology, were promising. Ambroxol was safe, caused no serious side effects, and was able to reach important levels in the brain. People in the placebo group showed worse psychiatric symptoms over time, but those taking Ambroxol stayed stable.
People with a certain gene variant called GBA1, which puts them at higher risk for Parkinson’s dementia, even showed better thinking and memory scores on the drug. Also, the marker for brain damage (GFAP) increased in the placebo group but stayed the same in the Ambroxol group, suggesting the medicine might help protect brain cells.
Although Ambroxol is approved for use in Europe for coughs and other breathing problems, it is not approved for any use in Canada or the U.S. yet. Dr. Pasternak says that current medications for Parkinson’s and dementia can only treat the symptoms, not the cause of the disease.
He believes Ambroxol could offer a new way to help people, especially those at high genetic risk. More research is needed, but the early signs are hopeful.
Ambroxol works by supporting an enzyme called GCase, which helps clear waste from brain cells. This enzyme is made by the GBA1 gene. In Parkinson’s patients, GCase levels are often too low. Without it, waste builds up and damages brain cells.
Pasternak learned about Ambroxol while working at SickKids hospital in Toronto, where it was being studied as a treatment for Gaucher disease—a rare childhood condition caused by low GCase.
Now, he’s using that knowledge to see if Ambroxol could also help adults with Parkinson’s-related dementia. He says the impact of this disease on families is enormous, and any new treatment could make a big difference.
The study was supported by the Weston Foundation and is an important step toward new treatments for Parkinson’s disease, dementia with Lewy bodies, and other brain-related conditions. Dr. Pasternak and his team are planning another clinical trial that will focus more closely on memory and thinking in the year ahead.
If you care about dementia, please read studies about Early heart rhythm problem linked to higher dementia risk and findings of Green leafy vegetables may help reduce Alzheimer’s risk.
For more about dementia, please read studies about Research shows an important cause of frontotemporal dementia and findings of New way to detect Lewy body disease early, a leading cause of dementia.
The study is published in JAMA Neurology.
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