Force-feeding is the practice of feeding a human or animal against their will. The term gavage refers to supplying a substance by means of a small plastic feeding tube passed through the nose (nasogastric) or mouth (orogastric) into the stomach.
A suffragette is force-fed in HM Prison Holloway in the UK during hunger strikes for women's suffrage, approximately 1911.
Clipping from World Magazine, September 6, 1914
1911 Votes for Women poster about William Ball (suffragist)
Guantanamo captives who will not comply with force-feeding have their arms, legs and head restrained in a feeding chair. They remain strapped in the chair until the nutrient is digested, to prevent induced vomiting.
Involuntary treatment refers to medical treatment undertaken without the consent of the person being treated. Involuntary treatment is permitted by law in some countries when overseen by the judiciary through court orders; other countries defer directly to the medical opinions of doctors.
Man in restraint chair in an English asylum in 1869
Standard modern day restraints
Inducements such as access to cigarettes are used as leverage to encourage patients to accept treatment.
Some Jehovah's Witnesses will choose to die rather than accept blood transfusions.