Thiazide Diuretics
� Thiazide diuretics are related structurally to the
antibacterial sulfonamides.
� A few thiazides differ slightly in chemical structure.
� These drugs are called thiazide-related diuretics.
� Prototype drug: hydrochlorothiazide (HydroDIURIL) (HCTZ)
� Pharmacotherapeutics
- Used in the treatment of hypertension; often first choice
� Pharmacokinetics
- Administered: oral. Metabolism: liver. Excreted: kidneys.
� Pharmacodynamics
- Acts in the distal tubule.
- It increases excretion of sodium and chlori
� Hydrochlorothiazide is more effective in which ethnic group?
- A. Europeans
- B. Chinese
- C. African Americans
- D. Mexican Americans
- C. African Americans
- In African Americans, hydrochlorothiazide therapy is
somewhat more effective than in patients who are of
European descent. It is believed that hypertensive
African Americans have features that are consistent
with volume and sodium
Loop Diuretics
� The loop diuretics work in the loop of Henle to inhibit re-
absorption of sodium and chloride.
� They exert a powerful effect on fluid and electrolyte
balance.
� Loop diuretics are sometimes referred to as high-ceiling
diuretics because the maximum diur
� Prototype drug: furosemide (Lasix)
� Pharmacotherapeutics
- Used to treat peripheral & pulmonary edema & HTN.
� Pharmacokinetics
- Administered: IV or oral. Highly protein-bound drug.
Excreted: kidneys.
� Pharmacodynamics
- Inhibits the reabsorption of sodium, chloride, and
water in the as
� The patient who is malnourished is at greater risk for toxicity from furosemide than the well-nourished patient?
- A. True
- B. False
- A. True
- This is true because the malnourished patient has
less protein in the body, which will result in more
free drug. Furosemide is a highly protein-bound
drug.
Potassium-Sparing Diuretics
� The potassium-sparing diuretics promote sodium and water excretion in the distal tubule.
� At the same time, potassium is not excreted; rather, it is
reabsorbed.
� This group of drugs produces weak diuresis and
antihypertensive effects when used alone.
� Prototype drug: triamterene (Dyrenium)
� Pharmacotherapeutics
- Used as an adjunct to manage edema and hypertension.
� Pharmacokinetics
- Absorbed incompletely after oral administration.
Metabolized: liver. Excreted: kidneys.
� Pharmacodynamics
- Inhibiting transport of sodium in the distal tu