Frusemide (Furosemide)

Indications

Frusemide (Furosemide) is used for: Hypertension, Congestive heart failure, Nephrotic syndrome, Hypercalcemia, Edema, Cirrhosis, Renal impairment, Cerebral/pulmonary edema, Pulmonary oedema, Acute renal failure, Chronic renal failure

Adult Dose

Oral Resistant Hypertension Adult: 20-80 mg PO divided q12hr Edema Edema associated with congestive heart failure (CHF), liver cirrhosis, and renal disease, including nephrotic syndrome 20-80 mg PO once daily; may be increased by 20-40 mg q6-8hr; not to exceed 600 mg/day Elderly: Initially, 20 mg and titrate upward if needed. Parenteral Oedema associated with heart failure Adult: 20-40 mg IV/IM once; may be increased by 20 mg q2hr; individual dose not to exceed 200 mg/dose Refractory CHF may necessitate larger doses Acute Pulmonary Edema/Hypertensive Crisis/Increased Intracranial Pressure 0.5-1 mg/kg (or 40 mg) IV over 1-2 minutes; may be increased to 80 mg if there is no adequate response within 1 hour;not to exceed 160-200 mg/dose Hyperkalemia in Advanced Cardiac Life Support (ACLS) 40-80 mg IV Hypermagnesemia in ACLS 20-40 mg IV q3-4hr PRN Hepatic impairment: Monitor, especially with high dosages

Child Dose

Edema Infants and children: 1-2 mg/kg IV/IM/PO once initially; increased by 1-2 mg/kg q6-8hr (PO) or 1 mg/kg q2hr (IV/IM); individual dose not to exceed 6 mg/kg Neonates (<28 days): 0.5-1 mg/kg IV/IM q8-24hr; individual dose not to exceed 2 mg/kg Resistant Hypertension <1 year: Safety and efficacy not established 1-17 years: 0.5-2 mg/kg PO q24hr or q12hr; individual dose not to exceed 6 mg/kg/dose

Renal Dose

Acute renal failure: 1-3 g/day may be necessary to attain desired response; avoid use in oliguric states

Administration

May be taken with or without food. May be taken w/ meals to reduce GI discomfort.

Contra Indications

Severe sodium and water depletion, hypersensitivity to sulphonamides and furosemide, hypokalaemia, hyponatraemia, precomatose states associated with liver cirrhosis, anuria or renal failure. Addison's disease.

Precautions

Prostatic hyperplasia. Hepatic or renal impairment, gout, DM, impaired micturition. Infusion rate should not exceed 4 mg/min to reduce the risk of ototoxicity. Monitor fluid and electrolyte balance and renal function. May lower serum levels of calcium and magnesium, thus serum levels should be monitored. Pregnancy and lactation. Lactation: Drug excreted into breast milk; use with caution; may inhibit lactation

Pregnancy-Lactation

Pregnancy category: C; treatment during pregnancy necessitates monitoring of fetal growth because of risk for higher fetal birth weights Lactation: Drug excreted into breast milk; use with caution; may inhibit lactation

Interactions

Analgesics reduce natriuretic action of furosemide. Antagonises hypoglycaemic agents and drugs used for gout. Hyperglycaemia with antihypertensive agent diazoxide. Antagonises muscle relaxants. Increased risk of ototoxicity when used with aminoglycosides especially in renal impairment. May enhance nephrotoxicity of cephalosporins. Effects of antihypertensives enhanced. Action antagonised by corticosteroids. Phenytoin and indometacin may reduce effects of furosemide. Potentially Fatal: May provoke severe hypotensive response with ACE inhibitors. NSAIDs inhibit diuretic and antihypertensive effects. Increased incidence of premature beats with cardiac glycosides.

Adverse Effects

Side effects of Frusemide (Furosemide) : >10% Hyperuricemia (40%), Hypokalemia (14-60%) Frequency Not Defined Hyponatraemia, hypochloraemic alkalosis, headache, drowsiness, muscle cramps, hypotension, dry mouth, thirst, weakness, lethargy, restlessness, oliguria, GI disturbances, hypovolaemia, dehydration, hyperuricaemia, acute generalised exanthematous pustulosis, drug rash w/ eosinophilia and systemic symptoms, reversible or irreversible hearing impairment, deafness, tinnitus, severe anaphylactic or anaphylactoid reactions (e.g. w/ shock), Stevens-Johnson syndrome, toxic epidermal necrolysis; increased liver enzyme, cholesterol and triglyceride serum levels. Potentially Fatal: Serious cardiac arrhythmias.

Mechanism of Action

Furosemide inhibits reabsorption of Na and chloride mainly in the medullary portion of the ascending Loop of Henle. Excretion of potassium and ammonia is also increased while uric acid excretion is reduced. It increases plasma-renin levels and secondary hyperaldosteronism may result. Furosemide reduces BP in hypertensives as well as in normotensives. It also reduces pulmonary oedema before diuresis has set in.