Thiazides and related Diuretics

Question 1

Thiazide Effects

Answer 1

similar to those of loop diuretics; increase renal excretion of Na, Cl, K & water
-elevate plasma levels of uric acid & glucose

Question 2

Difference between Loop diuretics and Thiazides

Answer 2

-the maximum diuresis produced by thiazides is considerably lower than the maximum diuresis produced by the loop diuretics
-thiazides cannot be effective when urine flow is decreased

Question 3

Thiazide prototype

Answer 3

Hydrochlorothiazide

Question 4

Thiazide Mechanism of Action & Pharmacokinetics

Answer 4

Mechanism of Action
promotes urine production by blocking the reabsorption of Na and Cl in the early segment of the distal convoluted tubule
-retention of Na and Cl in the nephron causes water to be retained as well, thereby producing an increased flow of urine

Pharmacokinetics
Diuresis begins about 2 hours after oral administrations
-effects peak within 4-6 hours
-most of the drug is excreted unchanged in urine

Question 5

Thiazide Therapeutic uses

Answer 5

-Essential hypertension
-Edema
-Diabetes insipidus
-protection against postmenopausal osteoporosis

Question 6

Thiazide Adverse effects

Answer 6

similar to loop diuretics with the exception that they are not ototoxic
-hyponatremia, hypochloremia, dehydration
-hypokalemia
-hyperglycemia
-hyperuricemia
-impact on lipids and magnesium

Question 7

other thiazides

Answer 7

-chlorothiazide
-methyclothiazide