Could an antidepressant medication that’s already on the market help prevent Alzheimer’s disease? Maybe.

A new study shows the drug citalopram [sye tal’ oh pram] reduced production of the protein beta-amyloid by nearly 40 percent in people without the disease. Beta-amyloid is thought to cause Alzheimer’s disease by clumping together and sticking to parts of the brain, preventing it from working properly.

To date, medicine has no effective way to stop these proteins from being produced. But if production could be slowed, it might help people avoid the disease.

In addition to testing the drug in healthy people, researchers also tested its use in mice bred to develop Alzheimer’s disease. Mice who received the medication had significantly fewer new protein plaques. Also, the plaques they did have grew slower than normal.

The researchers say what really works against beta amyloid is serotonin, a chemical that helps the brain and body run properly. Serotonin is heavily tied to mood and essential functions such as sleeping and control of temperature and appetite.

Citalopram encourages the brain to make more serotonin, which helps some people struggling with depression. It also appears to fight the Alzheimer’s-causing proteins.

While this research certainly sounds promising, there are some important factors to consider. The idea of preventing Alzheimer’s disease with citalopram needs more study before it can be seen as a viable option.

Also, the people and animals in the study received high doses of the medication, more than normally prescribed. Understanding the long-term effects of these doses will require extra research.

The verdict is out on this would-be preventive medicine, but research like this study can still shed light on Alzheimer’s disease.