Also, and this depends on the jurisdiction, but people can be forced to take psychiatric medication against their will. Or even forced to go through a treatment like ECT, for example when presenting with strong and dangerous mania. BTW, ECT has an extremely unfair popular opinion, it's one of the best treatments in all of psychiatry. It could even be that it is impossible to get a response from the patient, for example if they are catatonic and don't budge within a reasonable time - you just inject them with benzodiazepines, as this is a serious condition if left to last a long time.