Just... don't do this.

By Dr. Roshini Raj
December 07, 2015
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I used my friend's leftover medication—I've been prescribed the same kind in the past, so I know it works for me. Is that OK to do?

No! While your friend may take the same medicine as you did, the dose could be different, or it might no longer be the appropriate medication for you. When it comes to prescription drugs, you should never take one that was not prescribed to you at the time when you needed it. Not only are you risking potential side effects or drug interactions, but you may also be missing the correct remedy for your condition by trying to diagnose and treat yourself. If you think you need an Rx drug, see a doctor.

Health‘s medical editor, Roshini Rajapaksa, MD, is associate professor of medicine at the NYU School of Medicine and co-founder of Tula Skincare.