Furosemide Side Effects

Brand Names: Lasix

Please note - some side effects for Furosemide may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA at http://www.fda.gov/medwatch/ or 1-800-FDA-1088 (1-800-332-1088).

Side Effects of Furosemide - for the Consumer

Furosemide

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Furosemide:

Abnormal skin sensations; bladder spasm; blurred vision; constipation; cramping; dizziness; dizziness when rising from a seated or lying position; feeling of whirling motion; fever; headache; lightheadedness; mouth and stomach irritation; muscle spasm; nausea; redness; restlessness; ringing in the ears; seeing a yellow color; sensitivity to sunlight; vein inflammation.

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); confusion; diarrhea; drowsiness; dry mouth; excessive urination; hearing loss; loss of appetite; muscle pain/cramps/weakness; rapid or irregular heartbeat; restlessness; sudden joint pain; unusual bleeding or bruising; unusual thirst; unusual tiredness or weakness; vomiting; yellowing of the skin or eyes.

Furosemide Solution

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Furosemide Solution:

Dizziness; lightheadedness; sensitivity to sunlight.

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); calf pain or tenderness; confusion; dark urine; decreased or persistent increased urination; drowsiness; dry mouth; fast or irregular heartbeat; fever, chills, or sore throat; hearing decrease or loss; muscle pain/cramps/weakness; restlessness; ringing in the ears; severe or persistent nausea, vomiting, or dizziness; shortness of breath; sluggishness; stomach pain; unusual bleeding or bruising; unusual thirst or hunger; unusual tiredness or weakness; vein inflammation; yellow vision; yellowing of the skin or eyes.

Furosemide Tablets

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Furosemide Tablets:

Dizziness; lightheadedness; sensitivity to sunlight.

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); calf pain or tenderness; confusion; dark urine; decreased or persistent increased urination; drowsiness; dry mouth; fast or irregular heartbeat; fever, chills, or sore throat; hearing decrease or loss; muscle pain/cramps/weakness; restlessness; ringing in the ears; severe or persistent nausea, vomiting, or dizziness; shortness of breath; sluggishness; stomach pain; unusual bleeding or bruising; unusual thirst or hunger; unusual tiredness or weakness; vein inflammation; yellow vision; yellowing of the skin or eyes.

Furosemide Side Effects - for the Professional

Furosemide

Adverse reactions are categorized below by organ system and listed by decreasing severity.

Gastrointestinal System Reactions: 

1. pancreatitis
2. jaundice (intrahepatic cholestatic jaundice)
3. anorexia
4. oral and gastric irritation
5. cramping
6. diarrhea
7. constipation
8. nausea
9. vomiting

Systemic Hypersensitivity Reactio ns:

1. systemic vasculitis
2. interstitial nephritis
3. necrotizing angiitis

Central Nervous System Reactions:

1. tinnitus and hearing loss
2. paresthesias
3. vertigo
4. dizziness
5. headache
6. blurred vision
7. xanthopsia

Hematologic Reactions:

1. aplastic anemia (rare)
2. thrombocytopenia
3. agranulocytosis (rare)
4. hemolytic anemia
5. leukopenia
6. anemia

Dermatologic-Hypersensitivity Reactions:

1. exfoliative dermatitis
2. erythema multiforme
3. purpura
4. photosensitivity
5. urticaria
6. rash
7. pruritus

Cardiovascular Reaction:

Orthostatic hypotension may occur and be aggravated by alcohol, barbiturates or narcotics.

Other Reactions:

1. hyperglycemia
2. glycosuria
3. hyperuricemia spasm
4. muscle spasm
5. weakness
6. restlessness
7. urinary bladder
8. thrombophlebitis
9. fever

Whenever adverse reactions are moderate or severe, Furosemide dosage should be reduced or therapy withdrawn.

Side Effects by Body System

Cardiovascular

Volume depletion may predispose some patients to deep venous thrombosis.

In a study of patients with congestive heart failure (CHF) due to myocardial infarction, furosemide has been shown to decrease left ventricular end diastolic pressure and decrease peripheral vascular resistance before a significant increase in urine output or decrease in arterial blood pressure is observed.

However, in patients with advanced, chronic CHF, the IV administration of furosemide may result in an acute vasoconstrictor response associated with an acute increase in vasoconstrictive hormones, such as norepinephrine, renin, and arginine vasopressin (AVP).

After central venous catheter administration of furosemide 125 mg, 3rd degree AV heart block was observed in a very ill patient (one case report). Because no other etiology was found, it was believed that the relatively high pH of furosemide and/or the rapid rate of administration caused the arrhythmia.

Cardiovascular side effects have commonly included intravascular volume depletion and hypotension. Signs and symptoms of furosemide-induced volume depletion have included thirst, muscle cramps, weakness, dizziness, lightheadedness, syncope, tachycardia, palpitations, and dry skin. In addition, these signs and symptoms have often been associated with a hypochloremic metabolic alkalosis and increased serum BUN and creatinine.

Metabolic

Hyperuricemia is usually a benign side effect, but may be important in some patients with a history of gout.

Although less so than with thiazide diuretics, furosemide may induce a relative glucose intolerance, which may be important in some patients, such as diabetics.

Rare instances of hypocalcemia have been reported in patients with latent hypoparathyroidism, in which case both calcium and magnesium replacement may be helpful.

Metabolic abnormalities may be more likely and severe in patients with liver disease. If a patient has severe liver disease, frequent monitoring of the patient's electrolytes is recommended.

Calcium balance appears to remain neutral during treatment with a loop diuretic (i.e., furosemide, bumetanide). Although loop diuretics cause an increase in renal calcium excretion, this appears to be compensated for by a parathyroid-dependent increase in 1,25-dihydroxyvitamin D levels, which increases intestinal calcium absorption. Bone metabolism does not appear to be significantly affected by loop diuretics.

Metabolic side effects including hypokalemia, hypomagnesemia, and an increase in serum uric acid, have been relatively common especially with higher doses. Although less common than with thiazide diuretics, mild hyperlipidemia and hypercholesterolemia have been associated with the use of furosemide. A single study suggests that chronic furosemide therapy is associated with clinically significant thiamine deficiency via urinary thiamine loss. This may be important in patients with congestive heart failure since thiamine deficiency may impair cardiac performance.

Furosemide has been reported to displace thyroxine (T4) from protein-binding sites. When administered in large intravenous doses (above 80 mg), a transient increase in serum free T4 concentrations and decrease in serum total T4 concentrations have been reported.

Hypersensitivity

Hypersensitivity reactions to furosemide have been uncommon. Rashes, fever, malaise, interstitial nephritis, and eosinophilia have been reported. Anaphylaxis has only rarely been associated with use of furosemide.

Furosemide contains a sulfur moiety, and may induce an allergic reaction in some patients with a history of sulfa sensitivity.

Rare cases of interstitial nephritis and hypersensitivity angiitis associated with furosemide have been reported.

Nervous system

The doses of furosemide in cases of tinnitus, vertigo, or deafness ranged from 0.24 grams IV given over 40 minutes to 3 grams IV in divided doses over 9 hours and 2 grams IV in a single dose. It is recommended that infusion rates not exceed 4 mg/min to minimize the risk of ototoxicity.

Ototoxicity may be more likely and more severe due in patients with renal insufficiency.

Nervous system side effects have included headaches and dizziness. Ototoxicity (tinnitus and deafness)--occasionally irreversible--has been rarely associated with the use of high dose furosemide.

Gastrointestinal

Gastrointestinal side effects have included hepatic encephalopathy in patients with hepatocellular insufficiency, pancreatitis, jaundice (intrahepatic cholestatic jaundice), anorexia, oral and gastric irritation, cramping, diarrhea, constipation, nausea, and vomiting.

Hepatic

Cholestatic jaundice may be important in patients with liver disease.

Hepatic side effects have included rare cases of cholestatic jaundice.

Hematologic

Hematologic abnormalities, such as thrombocytopenia, aplastic anemia, and leukopenia have been very rare.

Dermatologic

One patient experienced acute generalized exanthematic pustulosis a few hours after receiving intravenous furosemide.

Dermatologic reactions, such as bullous pemphigoid have been reported in rare cases. Exfoliative dermatitis, erythema multiforme, purpura, photosensitivity, urticaria, rash, and pruritus have also been reported.

At least two cases of Sweet syndrome related to use of furosemide have been reported. In one case, Sweet syndrome was characterized by low-grade fever, tender, papular, erythematous, nonpruritic skin lesions on the arms and thighs, and redness in the eyes with photophobia. Papuloerythroderma of Ofuji has also been associated with furosemide use.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date, and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This information does not endorse drugs, diagnose patients, or recommend therapy. This drug information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug of drug combination is safe, effective, or appropriate for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of information provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.