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Study Finds That the Antibiotic Minocycline May Reduce the Likelihood of Transitioning to Definite Multiple Sclerosis

June 1, 2017

  • Researchers in Canada have published results of a small phase 3 clinical trial showing that minocycline, a relatively inexpensive oral antibiotic commonly used to treat acne, can reduce the likelihood that someone with clinically isolated syndrome (CIS) -- experiencing initial neurological symptoms suggestive of MS -- will go on to develop full-blown multiple sclerosis.
  • Dr. Luanne Metz (University of Calgary) and colleagues across Canada tested minocycline against placebo in 142 people with CIS. After 6 months, those taking twice daily minocycline had a 28% reduced risk of developing definite MS, compared to those taking placebo, and also had reduced disease activity detected on MRI scans. The risk reduction is similar to what has been reported with other disease modifying treatments in CIS trials. These benefits were not sustained at 24 months.
  • In addition to its bacteria-killing action, minocycline has been shown to have anti-inflammatory and neuroprotective properties. The most common side effects were rash, dizziness and tooth discoloration. Minocycline carries several warnings including that it is not to be taken during pregnancy.
  • Additional larger clinical trials are needed to confirm the effectiveness of minocycline in MS and CIS. 
- Read more about this study, including FAQ, from the MS Society of Canada
- Access the paper in the New England Journal of Medicine
- Read more about CIS and FDA-approved therapies to treat it

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. Symptoms range from numbness and tingling to blindness and paralysis, and there is currently no cure for MS. The progress, severity and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are leading to better understanding and moving us closer to a world free of MS. An estimated 1 million people live with MS in the United States. Most people with MS are diagnosed between the ages of 20 and 50, and it affects women three times more than men.


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