DIURETICS SONG Hui
OUTLINE BACKGROUND CLASSIFICATION OF DIURETICS REVIEW AND QUESTIONS
BACKGROUND The essential of urine. How urine formation. Which ion play an important role in this procedure. Ald, ADH The action sites of diuretics. Look at the diagram
CLASSIFICATION High effect diuretics: Lasix Mediate effect: Thiazide diuretics Mild (Low)effect: K + sparing diuretics Osmotic diuretics: Mannitol Others
High effect diuretics High ceiling (loop) diuretics Agent furosemide (lasix) Action site thick ascending loop (AL) Mechanism 1. Cl K-Na-2Cl
High effect diuretics 2. PGE P.E. Cl Na Renal Blood Flow (RBF) P.K. Onset in 5 min by i.v. 30 min by p.o. t1/2=2hr last for 4-6 hr ADR Ototoxicity (etacrynic acid>lasix>bumetanide)
Mediate effect diuretics Thiazides Agent Hydrochlorothiazide (HCT) Action site Distal convoluted tubule (DCT) Mechanism Na-K-2Cl, CA, PDE
Mediate effect diuretics ADR Hypokalemia ---be careful when use with digitalis. Hyperuricemia--- compete with uric acid Hyperglycemia--- insulin Hypercalcemia--- Ca
Low effect diuretics K + sparing diuretics Agent Antisterone, Triamterene & amiloride Action site DCT & CT (Collecting Tubule) Mechanism 1. Ald-R 2. Na channel Na K
Low effect diuretics ADR Hyperkalemia, sex hormone like effects ( antisterone ) Others Carbonic anhydrase inhibitors ( acetazolamide ) H 2 O + CO 2 H + HCO inside cell Na outside cell CA
Osmotic diuretics Agents (characters) Mannitol, Glucose Action site PCT, AL; Vessels, gastrointestinal tract Mechanism 1. Hyperosmolarity 2. Blood volume RBF
Osmotic diuretics P.E. H 2 O ADR BV CHF Dehydration Hypernatremia
CLINIC USES of DIURETICS Edema CHF ARF Hypertension Poisoning Hypercalciuria Hypercalciumia Glaucoma Diabetes insipidus
ADR of Diuretics Pla. KPla. UricA Pla.Caototoxicit y others H.D (Lasix) _ + _ + BV _ M.D (HCT) _ + + _LDL + L.D (antisterone) + + _ _Sex H effects In common Hyponatremia, electrolyte imbalances
Review & questions The classes of diuretics. The mechanisms of each. The Common ADR of diuretics The common P.E of diuretics The clinic uses of diuretics. Why DM patients have a lot of urine?