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September 1960

Sequential Changes Evoked by Chlorothiazide in Hypertensive Patients

Author Affiliations


From the Research Division of the Cleveland Clinic Foundation and the Frank E. Bunts Educational Institute.

Arch Intern Med. 1960;106(3):316-320. doi:10.1001/archinte.1960.03820030004002

Enhanced responsiveness to ganglioplegic drugs occurring during short-term treatment with chlorothiazide has been attributed to increased vasomotor tone evoked by oligemia.1 Diuretic-induced oligemia also seems responsible for increased depressor responses to trimethapan (Arfonad) and decreased pressor responses to norepinephrine.2 Chlorothiazide alone can lower arterial pressure in some hypertensive patients,1-3 and this effect may result from a decrease of plasma volume. This report describes the oligemic and antihypertensive effects of the diuretic in hypertensive patients receiving the drug for varying periods. The results support the suggestion 1 that decreases of arterial pressure observed during short-term diuretic therapy result from decreases of plasma volume and not from a specific antihypertensive effect.

Methods  Studies were performed in 17 hypertensive patients hospitalized in the Research Ward of the Cleveland Clinic Hospital. Fifteen received a 100 mEq. sodium diet, and two—who had previously suffered from congestive cardiac failure—continued to take a 55

Supplied by Dr. John Beem, Merck Sharp and Dohme, Division of Merk & Co., Inc.
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