Side effect

Outcome that is secondary to the one intended

In medicine, a side effect is an unintended effect caused by a medicinal drug or other treatment's capacities or properties, and these effects are often adverse but sometimes beneficial. Herbal and traditional medicines also have side effects. A drug or procedure usually used for a specific effect may be used specifically because of a beneficial side-effect; this is termed "off-label use" until such use is approved.

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