Trial of a Sustained Release Form of Amitriptyline in the Treatment of Depressive Illness

Amitriptyline is a widely used antidepressant and its effectiveness has been shown, e.g. in comparison with imipramine in double blind trial (Burt et al., 1962; Hordern et al., 1963, 1964). A disadvantage of currently prescribed tricyclic antidepressants is the necessity for administering the drug three times a day. It has been shown that general medical and in particular psychiatric patients fail to take their medication either in the prescribed dose or at all (Benstead and Theobald, 1952; Haler, 1952; Park and Lipman, 1964; Parkes et al., 1962; Porter, 1969). This failure rate may be as high as 50 per cent (Dixon et al., 1957; Willcox et al., 1965). Even in psychiatric in-patient studies there was still a high failure rate in taking prescribed psychiatric drugs (Hare and Willcox, 1967). A regimen consisting of a single daily dose is more reliably taken than one consisting of thrice daily dosage (Coppen et al., 1969; General Practitioner Clinical Trial 1970).