How Do People Taking Psychiatric Drugs Explain Their “Chemical Imbalance?”

Many people believe that chemical imbalances cause mental illnesses, despite the absence of evidence to ascertain this. This study describes the reasoning that people use in their own case to justify this belief. Data come from recorded medication histories with 22 adults aged 23–68 years, taking different psychiatric drugs for various problems and varying durations, asked directly if they thought their problem was caused by a chemical imbalance and to explain their answer. About two-thirds expressed belief that they had a chemical imbalance; and the rest that they did not have one, did not or could not know, or that their medication had caused one. Reasoning backward from positive drug experiences (ex juvantibus or post hoc) and appeals to authority and convention characterized most answers expressing belief in an imbalance. Experiencing improvement while taking drugs and acquiescing in mental health practitioners' views instills or reinforces people's belief that they are or were chemically imbalanced, which suggests viewing the belief as a drug effect. The chemical imbalance notion is likely to persist, as its appeal to give personal meaning to symptom relief and its unfalsifiability ensure institutional support that neutralizes the absence of scientific support.