unit 8 flashcards Diuretics and Antispasmodics

Flashcards covering Diuretics and Antispasmodics, including classifications, mechanisms of action, and key effects.

Diuretics

Drugs that increase the excretion of urine; all have an effect on sodium and water balance.

Edema

Abnormal accumulation of fluid in the interstitial spaces of tissue.

Diuretic Classification

Diuretics classified based on site of action, chemical structure, and potency; types include Carbonic Anhydrase Inhibitors, Loop diuretics, K+ sparing diuretics, Osmotic diuretics, and Thiazide diuretics.

Carbonic Anhydrase Inhibitors (CAI)

Non-bacteriostatic sulfonamides that inhibit the enzyme carbonic anhydrase, resulting in the excretion of sodium, potassium, and water; used for glaucoma and edema.

Loop Diuretics (Furosemide/Lasix)

A common diuretic, potent in action with a rapid onset, used to manage edema from heart failure, kidney disease, and liver disease; also manages HTN and hypercalcemia.

Loop Diuretics Mechanism of Action

Act on the ascending loop of Henle; blocks chloride and sodium reabsorption, leading to loss of electrolytes in urine; activates kidney prostaglandins, causing dilation of blood vessels.

Other Major Effects of Loop Diuretics

Electrolyte losses including hyponatremia, hypokalemia, and hypocalcemia as well as metabolic effects on blood glucose.

Potassium Sparing Diuretics

Drugs that block aldosterone receptors through competitive binding, causing sodium and water to be excreted and potassium to be retained; used for HTN, hyperaldosteronism, and reversal of potassium losses.

Osmotic Diuretics

Osmotic pressure in the glomerular filtrate pulls water into renal tubules causing rapid diuresis reducing cellular edema and increasing urine production

Thiazide Diuretics

Inhibit the reabsorption of sodium, potassium, and chloride; causes relaxation of arterioles, leading to decreased peripheral vascular resistance; used for heart failure and HTN.

Antispasmodics

From the anticholinergic drug class; used for overactive bladder; decreases bladder contraction and increases constriction of internal sphincter; example: oxybutynin chloride (Ditropan).