Clonidine in the Treatment of Severe Hypertension

Despite intensive research, the range of effective medications in the treatment of hypertension remains limited. Critical review of large numbers of patients demonstrates a disturbing proportion who have inadequate control of blood pressure because of resistance, intolerable side effects or postural hypotension. Consequently, there is pressing need for new drugs which differ in their mode of action from those currently available which preserve homceostatic cardiovascular responses and have tolerable and rapidly reversible side effects. Preliminary trials (Bock et alii, 1966; Davidov et alii, 1967; Ng et alii, 1967; Barnett and Cantor, 1968; Raftos, 1969; Smet et alii, 1969) indicated that clonidine hydrochloride offered considerable promise as a major antihypertensive drug. Consequently, an extensive trial was carried out between 1968 and 1972 in the Sydney Hospital Cardiovascular Clinic, the results of which are presented in this paper.