1. An illness, injury, or fatality that is the direct result of medical intervention (doctor induced), ranging from inappropriate treatment to harmful drug interaction, misinterpretation of a lab test, or a fatal reaction to an injection of penicillin or other medication.

Adverse side effects and dangerous interactions between drugs are probably the most common types of iatrogenic illnesses.

2. Any adverse mental or physical condition induced in a patient through the effects of treatment by a physician or surgeon; for example, chemotherapy, often used to attenuate or cure a cancer, initiates a process that causes the individual to become severely ill.

In an elderly person, a fall can lead to the use of restraints and bedrest, which can cause thrombophlebitis [inflammation of a vein in conjunction with the formation of a thrombus (a blood clot that obstructs a blood vessel)].

The use of a Foley catheter for incontinence can create a urinary tract infection and septic shock.