A drug used to treat high blood pressure and prostate enlargement, Prazosin, can be used to guard the brain from any possible damage caused by post-traumatic stress disorder, depression, Alzheimer’s disease, and schizophrenia.

The drug that is prescribed as an antipsychotic medication has the ability to block the increase of glucocorticoids, the steroid hormones.

From Sciencedaily.com:

Scientists believe stress activates a neurochemical response in the brain that triggers the release of glucocorticoids in the brain, and that high levels of glucocorticoids in blood serum are associated with such psychiatric conditions as schizophrenia, depression, PTSD and Alzheimer’s disease. This mechanism has been linked to decreases in cognitive performance in older people who are not suffering from clinical dementia.

“Our hypothesis is that just being afraid of being blown up all the time means you have high levels of steroids all the time,” Berger said, referring to PTSD among military personnel.

Low levels of glucocorticoids have anti-inflammatory effects in the brain, but high levels can trigger inflammatory mechanisms that damage nerve cells by activating an enzyme that causes oxidative stress. Even a single exposure to a high dose of glucocorticoids can be sufficient to damage nerve cells: A previous study showed synthetic glucocorticoid therapy to treat autoimmune disorders such as rheumatoid arthritis can induce mood disorders, including psychosis, and cognitive impairment known as “steroid dementia” in severe forms.

The finding was disclosed by researchers at the Oregon Health & Science University and Portland Veterans Affairs Medical Center and the study was funded by the U.S. Department of Veterans Affairs.