An adverse reaction or complication caused by treatment from a healthcare professional is called:

The term that refers to an adverse reaction or complication caused by treatment from a healthcare professional is iatrogenic. This concept pertains to any unintended condition or negative effect that arises as a direct consequence of medical intervention, such as surgery, medication, or diagnostic procedures.

For instance, if a patient develops an infection following surgery, that infection would be considered iatrogenic as it was a result of the medical treatment itself. This term highlights the potential drawbacks of healthcare practices, emphasizing the importance of monitoring and mitigating risks associated with treatments.

The other terms do not fit this definition. Anaphylactic refers specifically to a severe allergic reaction, which may or may not be related to medical treatment. Nosocomial is used to describe infections acquired in a hospital setting, indicating a source rather than a cause from treatment. Idiopathic describes conditions that arise without a known cause, which does not involve any treatment-related origin.