• Posted March 19, 2025

Rare Hair Loss Condition Can Be Treated With Low Doses Of Antibiotic

Lower doses of a common antibiotic can curb hair loss caused by a rare skin condition, a new study says.

The antibiotic doxycycline is commonly used to treat lymphocytic scarring alopecia, a condition in which the body’s immune cells target hair follicles, researchers said.

But the relatively high doses of doxycycline used to prevent hair loss and scarring aren’t necessary, according to findings published March 18 in the Journal of the American Academy of Dermatology.

That means these patients can receive effective treatment without the nausea, vomiting and rashes that can accompany high doses of doxycycline, researchers said.

“Our findings suggest that physicians can prescribe lower doses of doxycycline to patients struggling with lymphocytic scarring alopecia without compromising the efficacy and anti-inflammatory benefit of the therapy,” co-lead researcher Carli Needle, a medical student at NYU Grossman School of Medicine in New York City, said in a news release.

For the study, researchers analyzed medical data for more than 240 men and women treated for lymphocytic scarring alopecia between 2009 and 2023.

About 27% of patients had been prescribed low doses of doxycycline, and 73% the traditional high doses, researchers said.

Results showed that lower doxycycline doses of around 20 milligrams twice daily were equally as effective as higher doses of up to 100 milligrams twice daily.

Specifically, there was no significant difference in scalp inflammation, perceived hair loss, and measurements of hair density, hair diameter and hairline recession, researchers said.

Fewer people taking lower doses reported side effects -- 12% compared to 23% of people on higher doses.

People on low doses also were more likely to stick with the antibiotic, with 16% stopping due to GI side effects compared with 25% in the high-dose group.

Lower doses of doxycycline also are more likely to protect overall gut health, Needle said. The antibiotic is known to be harmful to healthy gut bacteria, but lower doses have been shown less risky for the microbes.

“Our results offer another avenue for healthcare providers to protect patients from harm caused by unnecessary antibiotic use and address the rise of drug-resistant strains of microbes,” co-lead researcher Anna Brinks, a medical student at NYU Grossman School of Medicine, said in a news release.

More information

The Cleveland Clinic has more on scarring alopecia.

SOURCE: NYU Langone Health, news release, March 18, 2025