Finasteride, a hair loss treatment, might also decrease alcohol consumption

FDA Highlights by Bruce Sylvester – Researchers report that finasteride appears to reduce alcohol consumption in some men. The results were published online on June 13, 2013 by Alcoholism: Clinical & Experimental Research.

Michael S. Irwig, MD, assistant professor of medicine at The George Washington University and sole author of the study said, “Finasteride has not been used for alcohol reduction in humans; our study is among the first to look at its effects on drinking in humans.”

As background, Chuck Zorumski, MD, professor and head of the department of psychiatry at Washington University School of Medicine, St.Louis, Missouri,  added, “Finasteride is a 5α-reductase inhibitor that blocks the production of a variety of cholesterol-derived hormones and modulators, including certain androgens and other steroids that are active in both the body and brain. Neuroactive steroids like allopregnanolone help to regulate brain networks involved in emotion, motivation, and cognition. There is considerable interest in whether these neurosteroids contribute to psychiatric illnesses. Alcohol is known to augment the production of neurosteroids like allopregnanolone in animals, and these steroids are thought to contribute to the sedating, intoxicating, and adverse effects of alcohol, including acute memory impairment. The present study is important because it is the first study in humans to link clinical finasteride use to changes in alcohol consumption.”

The 83 men in the study had developed persistent sexual side effects associated with the use of finasteride, even though they had stopped taking the medication for at least three months. Irwig used standardized interviews to collect information about medical history, sexual function and alcohol-consumption before and after finasteride use.

Of the 63 men with persistent sexual side effects who drank at least one drink per week before using finasteride, 41 or 65 percent reported a decrease in alcohol consumption. “While studying the persistent sexual side effects associated with finasteride, we observed that the majority of the men had reduced their alcohol consumption,” said Irwig. “Many of these men completely stopped drinking alcohol, as drinking would affect them differently than before taking finasteride.”

Irwig reported that 18 of the 63 men became abstinent. The men reported problems tolerating alcohol following finasteride treatment, including increased anxiety, tiredness, dizziness, intoxication with fewer drinks, and less euphoria.”

Notably, Irwig cautioned against rushing to prescribe finasteride for the reduction of drinking. “It is unknown whether finasteride could suppress drinking in otherwise healthy men,” he said. “I hope that this study will generate more research on the effects of finasteride in humans as it relates to alcohol.”

“Until more systematic studies are done, clinicians should be alert to problems and side effects associated with the use of alcohol in patients treated with finasteride,” added Zorumski. “The findings should spur further studies both in humans and animals to determine the role of neurosteroids in a variety of neuropsychiatric disorders, including alcoholism, depression, and anxiety. For example, it will be important to examine whether finasteride enhances the toxicity of ethanol. However, results from Dr. Irwig’s cohort and previous animal studies raise intriguing possibilities about developing finasteride-type drugs for the treatment of alcohol abuse.”