What is contraindication?

Answer

A contraindication is any condition or circumstance where the use of a specific treatment or drug is not advised because it could harm the person.

Answer

In medicine, "contraindicated" is specifically used to indicate treatments or drugs which will make the patient's condition significantly worse. It is often used for drugs where this negative effect may not be immediately apparent, even to a trained medical professional.

For instance, treatment of strokes and similar blockages often uses blood thinners, which are effective in many patients. However, in the case of hemophiliacs, the use of such drugs is contraindicated because, while the medicine may help the stroke, it serious aggrevates the preexisting underlying hemophilia to such a degree that the drug is likely to do more harm to the patient than good.