Diuretics development

In the last ten years, the sulfonamide type of diuretic has yielded spectacularly to intensive study. The recognition that certain sulfonamides could have a useful influence upon renal electrolyte excretion is scarcely 15 years old The basic observations for this diuretic development arose from the sulfa drug era, from observations on the side effects of the first sulfa drug, sulfanilamide. Tishler (62) gives a chart depicting the many new drug fields where valuable... 

Drugs. Ttifluoromethyl-based pharmaceuticals had been limited to phenothiatine tranquilizers and benzothiadiazine 1,1-dioxide diuretics (qv). However, new dmgs have been developed (Table 11). One of the key properties of the CF group is its high lipophilicity it increases the Hpid solubiUty of the pharmaceutical and thus accelerates absorption and transport within the host organism. 

Ascites. Patients with cirrhosis, especially fiver cirrhosis, very often develop ascites, ie, accumulation of fluid in the peritoneal cavity. This is the final event resulting from the hemodynamic disturbances in the systemic and splanchnic circulations that lead to sodium and water retention. When therapy with a low sodium diet fails, the dmg of choice for the treatment of ascites is furosemide, a high ceiling (loop) diuretic, or spironolactone, an aldosterone receptor antagonist/potassium-sparing diuretic. 

Which electrolyte imbalance would the patient receiving a loop or thiazide diuretic most likely develop ... 

Develop a treatment plan to alleviate symptoms and maintain euvolemia with diuretics. Daily weights to assess fluid retention are recommended. 

Evaluate effectiveness of diuretic therapy with regard to ascitic fluid accumulation and development of peripheral edema. Ask the patient directed questions about abdominal girth, fullness, tenderness, and pain. Weigh the patient at each visit, and ask the patient to keep a weight diary. Assess for peripheral edema at each visit. 

Develop a plan to provide symptomatic care of complications associated with ARF, such as diuretic therapy to treat volume overload. Monitor the patient s weight, urine output, electrolytes (such as potassium), and blood pressure to assess efficacy of the diuretic regimen. 

Medications can increase the risk of hyperkalemia in patients with CKD, including angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers, used for the treatment of proteinuria and hypertension. Potassium-sparing diuretics, used for the treatment of edema and chronic heart failure, can also exacerbate the development of hyperkalemia, and should be used with caution in patients with stage 3 CKD or higher. 

Acute drug-related hypersensitivity reactions (allergic responses) may cause tubulointerstitial nephritis, which will damage the tubules and interstitium. These reactions are most commonly observed with administration of methicillin and other synthetic antibiotics as well as furosemide and the thiazide diuretics. The onset of symptoms occurs in about 15 days. Symptoms include fever, eosinophilia, hematuria (blood in the urine), and proteinuria (proteins in the urine). Signs and symptoms of acute renal failure develop in about 50% of the cases. Discontinued use of the drug usually results in complete recovery however, some patients, especially the elderly, may experience permanent renal damage. 

The signs and symptoms of bulimia are similar to those of anorexia. Other signs may include binge eating and inappopri-ate use of diuretics or laxatives. Cavities or gum infections may develop, or the enamel of the teeth may show signs of being stripped off, because of the frequent exposure to stomach acid. 

A patient develops hyperglycemia, hyperuricemia, and hypomagnesemia on which of the following diuretic agents ... 

The answer is c. (Hardman, pp 704-706J Triamterene produces retention of the K ion by inhibiting in the collecting duct the reabsorption of Na, which is accompanied by the excretion of K ions. The loop diuretics furosemide and bumetanide cause as a possible adverse action the development of hypokalemia. In addition, thiazides (e g, hydrochlorothiazide) and the thiazide-related agents (e.g., metolazone) can cause the loss of K ions with the consequences of hypokalemia. Triamterene can be given with a loop diuretic or thiazide to prevent or correct the condition of hypokalemia. 

The answer is a. (Hardman, pp 705-706.) Patients at increased risk of developing hyperkalemia should not receive K-sparing diuretics. Potassiumsparing diuretics appear to block Na channels in the luminal membrane of the late distal tubules and the collecting duct. A mild excretion of Na occurs because of the relatively low capacity to reabsorb it in this portion of the nephron. Loop diuretics and thiazides typically increase K excretion. 

Patients with sodium overload should be treated with loop diuretics (furosemide, 20 to 40 mg IV every 6 hours) and 5% dextrose at a rate that decreases serum sodium by approximately 0.5 mEq/L/hour or, if hypernatremia developed rapidly, 1 mEq/L/hour. 

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