BENZTHIAZIDE

Absorption

Absorbed in the digestive tract.

Toxicity

Symptoms of overdose include nausea, vomiting, fatigue, urinary problems and drowsiness.

Originator

Exna,Robins,US,1960

The Uses of BENZTHIAZIDE

Benzthiazide is a diuretic, antihypertensive agent.

Background

Benzthiazide is used to treat hypertension and edema. Like other thiazides, benzthiazide promotes water loss from the body (diuretics). They inhibit Na+/Cl- reabsorption from the distal convoluted tubules in the kidneys. Thiazides also cause loss of potassium and an increase in serum uric acid. Thiazides are often used to treat hypertension, but their hypotensive effects are not necessarily due to their diuretic activity. Thiazides have been shown to prevent hypertension-related morbidity and mortality although the mechanism is not fully understood. Thiazides cause vasodilation by activating calcium-activated potassium channels (large conductance) in vascular smooth muscles and inhibiting various carbonic anhydrases in vascular tissue.

Indications

For the treatment of high blood pressure and management of edema.

Definition

ChEBI: 7-Sulfamoyl-1,2,4-benzothiadiazine 1,1-dioxide in which the hydrogen at position 6 is substituted by chlorine and that at position 3 is substituted by a benzylsulfanylmethyl group. A diuretic, it is used to treat hypertension and edema.

What are the applications of Application

Benzthiazide is a diuretic and antihypertensive compound

Manufacturing Process

The preparation of the dihydro analog is as follows:
(A) Preparation of 3-Chloromethyl-6-Chloro-7-Sulfamyl-3,4-DihydroBenzothiadizine-1,1-Dioxide - To 8 ml of 40-50% chloroacetaldehyde aqueous solution and 7 ml of dimethylformamide are added 10 grams of 2,4- disulfamyl-5-chloroaniline. The mixture is heated on a steam bath for 2 hours after which it is concentrated at reduced pressure. The residue is triturated with water. The solid material is recrystallized from methanol-ether after treatment with activated carbon to give 7.2 grams of product, MP 229°- 230°C.
(B) Preparation of Benzylthiomethyl-6-Chloro-7-Sulfamyl-3,4- Dihydrobenzothiadiazine-1,1-Dioxide - A mixture of 3-(chloromethyl)-6-chloro- 7-sulfamyl-3,4-dihydrobenzothiadiazine-1,1-dioxide (0.02 mol) and benzylmercaptan (0.024 mol) in 20 ml of 10% sodium hydroxide and 20 ml of dimethylformamide is stirred at room temperature for 6 hours. After heating for 10 minutes on a steam bath, the mixture is cooled and acidified with 6 N HCl. The product, after recrystallization from acetone, melts at 210°-211°C.

brand name

Aquatag (Solvay Pharmaceuticals); Fovane (Pfizer).

Therapeutic Function

Diuretic, Antihypertensive

Pharmacokinetics

Benzthiazide is used to treat hypertension and edema. Like other thiazides, benzthiazide promotes water loss from the body (diuretics). They inhibit Na+/Cl- reabsorption from the distal convoluted tubules in the kidneys. Thiazides also cause loss of potassium and an increase in serum uric acid. Thiazides are often used to treat hypertension, but their hypotensive effects are not necessarily due to their diuretic activity. Thiazides have been shown to prevent hypertension-related morbidity and mortality although the mechanism is not fully understood. Thiazides cause vasodilation by activating calcium-activated potassium channels (large conductance) in vascular smooth muscles and inhibiting various carbonic anhydrases in vascular tissue.

Safety Profile

Poison by intravenous route. Adiuretic and antihypertensive agent. When heated todecomposition it emits very toxic fumes of SOx, NOx, andCl^-.

Metabolism

Not Available