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Medical Term:

adverse effect

Pronunciation: ad′vers e-fekt′

Definition: a result of drug or other therapy in addition to or in extension of the desired therapeutic effect; usually but not necessarily, connoting an undesirable effect. Although technically the therapeutic effect carried beyond the desired limit (a hemorrhage from an anticoagulant) is a side effect, the term more often refers to pharmacologic results of therapy unrelated to the usual objective (a development of signs of Cushing syndrome with steroid therapy).

Synonym(s): side effect