toxic

A "poisonous" but not necessarily lethal effect or concentration of a drug or other substance. This term can also be used to describe the state of a patient whose level of a drug is so high as to risk serious or dangerous adverse effects as when a patient is said to be "dilantin toxic." Physicians sometimes use the term interchangeably with delirium even when the cause is unknown or unrelated to a substance or drug.

• pharmacology