Oral diazoxide in uncontrolled malignant hypertension.

Abstract

Over the past 18 months, eight patients who had been referred with severe refractory hypertension have been treated with diazoxide given orally. Because of short supplies and recognized side effects we have reserved this treatment for patients whose blood pressure we were unable to control with large doses of other available hypotensive agents. The effect of diazoxide given orally on the blood pressure was dramatic; the blood pressure fell rapidly to normal or near normal levels in all cases. Hyperglycaemia and fluid retention have been the major side effects and the blood sugar may be difficult to control, swinging rapidly from hypoglycaemic levels to hyperglycaemia In relation to the administration or withdrawal of oral hypoglycaemic agents. Marked fluid retention and oedema may develop with control of the blood pressure and all patients required frusemide to control this side effect. Careful control of serum potassium levels is necessary especially when renal function is Impaired. Hirsuitism has developed in three cases and Parkinsonian features in one. Thus, in spite of the dramatic and predictable fall In blood pressure which was achieved, the side effects are such that oral treatment with diazoxie should be reserved for patients resistant to other forms of therapy. Careful clinical and biochemical supervision is also necessary.