Furosemide development

A 76-year-old female with an eight-year history of CHF that has been well controlled with digoxin and furosemide develops recurrence of dyspnea on exertion. On physical examination, she has sinus tachycardia, rales at the base of both lungs, and 4+ pitting edema of the lower extremities Which agent could be added to her therapeutic regimen ... 

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. 

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. 

A 65-year-old female receives digoxin and furosemide for GIF After several months, she develops nausea and vomiting. Serum K+ is 2.5 mFq/L. Electrocardiogram (EKG) reveals an AV conduction defect. What cellular effect is causing these new findings ... 

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. 

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. 

Menon A, Ritschel A, Sakr A. Development and evaluation of a monolithic floating dosage form for furosemide. J Pharm Sci 1994 83 239-245. 

Gastric lavage is contraindicated because of the serious danger of aspiration and the relatively benign gastrointestinal effects. Patients with respiratory difficulties require oxygen and sometimes mechanical ventilation. Pulmonary oedema, if it occurs, should be treated with diuretics (furosemide 25-100 mg intravenously) or by mechanical ventilation. Antibiotic treatment is unnecessary unless bacterial pneumonia, a rare sequel to kerosene pneumonitis, develops. Mortality is less than 1%. 

A 13-year-old girl with diabetes was given insulin 2 U/ kg/day. She developed generalized edema and gained 20 kg over 2 weeks. With less insulin, furosemide, and later ephedrine the edema disappeared within 1 month. 

A 14-year-old girl with diabetes was given insulin up to 1.5 U/kg/day and gradually developed edema and gained 8.5 kg over 9 days. With furosemide, the edema gradually disappeared in 1 month. 

A 67-year-old man, who had taken amiodarone 200 mg/ day for 3 months, developed hyponatremia (serum sodium concentration 117 mmol/1) (27). He was also taking furosemide 20 mg/day, spironolactone 25 mg/ day, and lisinopril 40 mg/day. His urine osmolality was 740 mosmol/kg with a normal serum osmolality. Fluid restriction was ineffective, but when amiodarone was withdrawn the sodium rose to 136 mmol/1. 

Loop diuretics, the next class of diuretic drugs to be developed, are also the most potent. Their introduction was a major advance in the treatment of congestive heart failure. Furosemide (Lasix), the first of the loop diuretics, debuted in 1965. 

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