Medical torture describes the involvement and sometimes active participation of medical professionals in acts of torture, either to judge what victims can endure, to apply treatments which will enhance torture, or as torturers in their own right. Medical torture may be called medical interrogation if it involves the use of their expert medical knowledge to facilitate interrogation or corporal punishment, in the conduct of torturous human experimentation or in providing professional medical sanction and approval for the torture of prisoners. Medical torture also covers torturous scientific (or pseudo-scientific) experimentation upon unwilling human subjects.
- Between 1937 and 1945, Japanese medical personnel who were part of Unit 731 participated in the torture killings of as many as 10,000 Chinese, Russian, American and other prisoners as well as Allied POWs during the second Sino-Japanese War.
- During World War II, Unit 731 of the Japanese Imperial Army tried out various biological weapons on Chinese subjects.
- During World War II, the Nazi regime in Germany conducted human medical experimentation on large numbers of people held in its concentration camps. In particular, Josef Mengele's experiments on prisoners at Auschwitz earned him the nicknames "the Angel of Death" and "Dr. Death".
- Japanese surgeons also performed vivisection and other medical experiments to torture American prisoners of war in several islands of the Pacific.  
- Between 1970 and 1971, mentally disorienting interrogation techniques were used against interned prisoners captured in Northern Ireland, including white noise. The Irish government complained to the European Commission for Human Rights, who found Britain guilty of torture; however the higher European Court of Human Rights ruled that the British government's actions were "inhuman and degrading but did not constitute torture". 
- In Soviet mental hospitals, used to hold political prisoners, very unpleasant medications were given to these "patients" as a means of punishment. A psychiatric diagnosis was devised to describe people who oppose government policies.
- In 1978, "Pisaot menuh" ("Human Experiments") were performed on seventeen political prisoners held at the infamous prison Tuol Sleng in Phnom Penh under the Khmer Rouge.
- A study called "The Aversion Project" found that gay conscripts in the South African Defence Forces (SADF) during the apartheid era had been forced to submit to "curing" their homosexuality, both by electroshock therapies and by botched sex changes.
- There have been numerous claims that electroconvulsive therapy and prefrontal lobotomies and similar psychiatric treatments have sometimes been performed not in the patient's best interests, but rather as punishment for misbehaviour or to otherwise make the patient easier to manage. A classic example of this is the Lake Alice, New Zealand atrocity which occurred in the early 1970s. Children admitted to the Lake Alice Hospital's open child and adolescent unit were routinely punished with unmodified electroconvulsive treatment. Some governments (e.g.Norway and New Zealand) have since begun paying reparations to patients who suffered such treatments. The World Health Organization has called for a ban on unmodified ECT, and states no form of it should be used on children.