Overdose of Tricyclic Anti-Depressants and Deductions Concerning their Cerebral Action

Abstract

The tricyclic antidepressant drugs are established therapeutic agents, yet their mode of action has remained obscure. The usual delay of some 10 or more days before they produce beneficial effects has never been satisfactorily explained. Many months are usually necessary for lasting cure, for often symptoms recur when the drugs are stopped. If they are then reinstated for several months, and then stopped, the patient commonly remains free of symptoms. There is thus uncertainty as to whether the drugs might simply be masking the depression in a manner comparable to anxiety-relieving agents, and uncertainty whether patients should be regarded as temporarily dependent upon tricyclic drugs. Slow brain processes have to be inferred, of a duration often met in psychiatry (Oswald, 1967). The observations we now report have features in common with many other slow brain recovery processes Oswald, 1969) and may cast light upon the mode of action of antidepressant drugs, as well as providing further insight into the chemical mechanisms of sleep. The latter are currently believed to be governed in part by cerebral mono-amines, which the tricyclic drugs are thought to affect.