DEMONSTRATION of a humorally mediated pressor mechanism of centralnervous origin1 prompted the suggestion that this system might sometimes participate in the genesis of essential hypertension. Since the pressor effect was suppressed by "apresoline" (1-hydrazinophthalazine, Ciba), it was considered possible that patients in whom the mechanism was operative would respond favorably and relatively specifically to treatment with this drug. It was recognized that the drug has properties which might tend to decrease arterial pressure by other means than inhibition of cerebral pressor activity.
With these considerations in mind, a survey was initiated of the therapeutic effects of "apresoline" when administered as the sole antipressor agent to patients suffering from a wide spectrum of hypertensive disease.
METHOD OF STUDY
Ninety-seven patients were treated with "apresoline" for at least 3 months and usually for 12 months or more. Of these, 58 were hospitalized for close observation and at least preliminary treatment; as