Furosemide

Furosemide Uses, Dosage, Side Effects, Food Interaction and all others data.

Furosemide is a monosulphonyl diuretic. It is an effective diuretic that retains its activity even in low glomerular filtration rate (GFR). Furosemide has a distinctive action on renal tubular function. It affects a peak diuresis far greater than that observed with other agents. Other features are (I) prompt onset of action (II) inhibition of sodium and chloride transport in the ascending limb of the loop of Henle and (III) independence of their action from acid-base balance changes. Furosemide acts primarily to inhibit electrolyte reabsorption in the thick ascending limb of the loop of Henle. Furosemide is readily absorbed from the gastrointestinal tract and considerable proportions are bound to plasma proteins. It is rapidly excreted in the urine. With an hour after intravenous injection, its effect is evident in about 5 minutes and last for about 2 hours.

Furosemide manages hypertension and edema associated with congestive heart failure, cirrhosis, and renal disease, including the nephrotic syndrome. Furosemide is a potent loop diuretic that works to increase the excretion of Na+ and water by the kidneys by inhibiting their reabsorption from the proximal and distal tubules, as well as the loop of Henle. It works directly acts on the cells of the nephron and indirectly modifies the content of the renal filtrate. Ultimately, furosemide increases the urine output by the kidney. Protein-bound furosemide is delivered to its site of action in the kidneys and secreted via active secretion by nonspecific organic transporters expressed at the luminal site of action.

Following oral administration, the onset of the diuretic effect is about 1 and 1.5 hours , and the peak effect is reached within the first 2 hours. The duration of effect following oral administration is about 4-6 hours but may last up to 8 hours. Following intravenous administration, the onset of effect is within 5 minutes, and the peak effect is reached within 30 minutes. The duration of action following intravenous administration is approximately 2 hours. Following intramuscular administration, the onset of action is somewhat delayed.

Trade Name Furosemide
Availability Prescription only
Generic Furosemide
Furosemide Other Names Frusemide, Furosemid, Furosemida, Furosemide, Furosemidu, Furosemidum
Related Drugs amlodipine, lisinopril, metoprolol, losartan, carvedilol, hydrochlorothiazide, spironolactone, warfarin, atenolol, Lasix
Weight 20mg, 40mg, , 10mg/ml, 20mg/2ml
Type Tablet, Injection
Formula C12H11ClN2O5S
Weight Average: 330.744
Monoisotopic: 330.007719869
Protein binding

Plasma concentrations ranging from 1 to 400 mcg/mL are about 91-99% bound in healthy individuals. The unbound fraction is about 2.3-4.1% at therapeutic concentrations. Furosemide mainly binds to serum albumin.

Groups Approved, Vet approved
Therapeutic Class Loop diuretics
Manufacturer Eskayef Bangladesh Ltd, Premier Pharmaceuticals Ltd, Baxter Healthcare Ltd, Farmasi,  quatum Laboratories Internasional, Ipha Laboratories, Dexa Medica, Indofarma, Bernofarm, Mersifarma Tirmaku Mercusana, Ethica Industri Farmasi, Shandong Xier Kangtai Pharm Co Ltd
Available Country Bangladesh, United Kingdom, United States, Indonesia, Netherlands, China, Nigeria
Last Updated: September 19, 2023 at 7:00 am
Furosemide
Furosemide

Uses

Tablet: Frusemide is a diuretic recommended for use in all indications when a prompt and effective diuresis is required. Indications for Frusemide 40 mg include cardiac, pulmonary, hepatic and renal oedema, peripheral edema due to mechanical obstruction or venous insufficiency and hypertension.

Injection: Frusemide is a diuretic recommended for use when a prompt and effective diuresis is required. The intravenous formulation is appropriate for use in emergencies or when oral therapy is precluded. Indications include cardiac, pulmonary, hepatic and renal oedema.

Furosemide is also used to associated treatment for these conditions: Acute Pulmonary Edema, Ascites, Body Fluid Retention, Edema, High Blood Pressure (Hypertension), Mild to Moderate Hypertension

How Furosemide works

Furosemide promotes diuresis by blocking tubular reabsorption of sodium and chloride in the proximal and distal tubules, as well as in the thick ascending loop of Henle. This diuretic effect is achieved through the competitive inhibition of sodium-potassium-chloride cotransporters (NKCC2) expressed along these tubules in the nephron, preventing the transport of sodium ions from the lumenal side into the basolateral side for reabsorption. This inhibition results in increased excretion of water along with sodium, chloride, magnesium, calcium, hydrogen, and potassium ions. As with other loop diuretics, furosemide decreases the excretion of uric acid.

Furosemide exerts direct vasodilatory effects, which results in its therapeutic effectiveness in the treatment of acute pulmonary edema. Vasodilation leads to reduced responsiveness to vasoconstrictors, such as angiotensin II and noradrenaline, and decreased production of endogenous natriuretic hormones with vasoconstricting properties. It also leads to increased production of prostaglandins with vasodilating properties. Furosemide may also open potassium channels in resistance arteries. The main mechanism of action of furosemide is independent of its inhibitory effect on carbonic anhydrase and aldosterone.

Dosage

Furosemide dosage

Tablet-

Edema:

  • Adults: The initial adult dose is 40 mg daily, reduced to 20 mg daily or 40 mg on alternate days. In some patients daily doses of 80 mg or higher (given in divided doses) may be required. The individually determined single dose should then be given once or twice daily (eg, at 8 am and 2 pm). For resistant edema, 80-120 mg daily. In patients with clinically severe edematous states the dose of furosemide may be carefully titrated up to 600 mg/day. When doses exceeding 80 mg/day are given for prolonged periods, careful clinical observation and laboratory monitoring are particularly advisable.
  • Neonate: 0.5-2 mg/kg every 12-24 hours (every 24 hours if postmenstrual age under 31 weeks).
  • Child 1 month-12 years: 0.5-2 mg/kg 2-3 times daily (every 24 hours if postmenstrual age less than 31 weeks); higher doses may be required in resistant edema; max. 12 mg/kg daily, not to exceed 80 mg daily.
  • Child 12-18 years: 20-40 mg daily, increased in resistant edema to 80-120 mg daily.
  • Elderly: In the elderly furosemide is generally eliminated more slowly. Dosage should be titrated until the required response is achieved.

Hypertension: 

  • Adults: The usual initial dose of furosemide for hypertension is 80 mg, usually divided into 40 mg twice a day. Dosage should then be adjusted according to response. If response is not satisfactory, add other antihypertensive agents. Children: The usual dose is 1-3 mg/kg body weight daily up to a maximum dose of 40 mg/day.
  • Elderly: In the elderly furosemide is generally eliminated more slowly. Dosage should be titrated until the required response is achieved.

Injection-

Edema: 

  • Adults: Doses of 20-50 mg intramuscularly or intravenously may be given initially. If larger doses are required, they should be given increasing by 20 mg increments and not given more often than every two hours. If doses greater than 50 mg are required it is recommended that they should be given by slow intravenous infusion. The recommended maximum daily dose of furosemide administration is 1,500 mg.
  • Neonate: 0.5-1 mg/kg every 12-24 hours (every 24 hours if postmenstrual age under 31 weeks).
  • Child 1 month-12 years: 0.5-1 mg/kg repeated every 8 hours as necessary; maximum 2 mg/kg (max. 40 mg) every 8 hours.
  • Child 12-18 years: 20-40 mg repeated every 8 hours as necessary; higher doses may be required in resistant cases.
  • Child 1 month-18 years: By continuous intravenous infusion: 0.1-2 mg/kg/hour (following cardiac surgery, initially 100 micrograms/kg/hour, doubled every 2 hours until urine output exceeds 1 mL/kg/hour).
  • Elderly: In the elderly furosemide is generally eliminated more slowly. Dosage should be titrated until the required response is achieved.

Hypertension: 

  • Adults: Doses of 20 to 50 mg intramuscularly or intravenously may be given initially. If larger doses are required, they should be given increasing by 20 mg increments and not given more often than every two hours.
  • If doses greater than 50 mg are required it is recommended that they should be given by slow intravenous infusion. The recommended maximum daily dose of furosemide administration is 1,500 mg. Children: Parenteral doses for children range from 0.5-1.5 mg/kg body weight daily up to a maximum total daily dose of 20 mg.
  • Elderly: In the elderly furosemide is generally eliminated more slowly. Dosage should be titrated until the required response is achieved.

Tablet: May be taken with or without food. May be taken with meals to reduce GI discomfort.

Injection: Injection should be administered in children by slow intravenous injection

Side Effects

As with other diuretics, electrolytes and water balance may be disturbed as a result of diuresis of prolonged therapy. Prolonged use can produce alkalosis. It may also cause uric acid retention and may rarely produce acute gout. Furosemide may provoke hyperglycemia and glycosuria.

Toxicity

Clinical consequences from overdose depend on the extent of electrolyte and fluid loss and include dehydration, blood volume reduction, hypotension, electrolyte imbalance, hypokalemia, hypochloremic alkalosis, hemoconcentration, cardiac arrhythmias (including A-V block and ventricular fibrillation). Symptoms of overdose include acute renal failure, thrombosis, delirious states, flaccid paralysis, apathy and confusion. In cirrhotic patients, overdosage might precipitate hepatic coma.

In rats, the oral LD50, intraperitoneal LD50, and subcutaneous LD50 is 2600 mg/kg, 800 mg/kg, and 4600 mg/kg, respectively. The Lowest published toxic dose (TDLo) in a female is 6250 μg/kg.

Precaution

Patients with prostatic hypertrophy or impairment of micturition have an increased risk of developing acute retention. A marked fall in blood pressure may be seen when ACE inhibitors are added to furosemide therapy. The toxic effects of nephrotoxic antibiotics may be increased by concomitant administration of potent diuretics such furosemide.

Interaction

A marked fall in blood pressure may be seen when ACE inhibitors are added to furosemide therapy. Serum lithium levels may be increased when lithium is given concomitantly with furosemide. The toxic effects of nephrotoxic antibiotics may be increased by concomitant administration of potent diuretics such as furosemide.

Food Interaction

  • Avoid excessive or chronic alcohol consumption. Alcohol increases the risk of orthostatic hypotension.
  • Avoid natural licorice. Avoid licorice in large amounts, as it may lead to hypokalemia.
  • Increase consumption of potassium-rich foods. This medication may cause potassium depletion. Foods containing potassium include bananas and orange juice.

Furosemide Alcohol interaction

[Moderate]

Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation.

Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

Caution and close monitoring for development of hypotension is advised during coadministration of these agents.

Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs.

Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.

Volume of Distribution

The volume of distribution following intravenous administration of 40 mg furosemide were 0.181 L/kg in healthy subjects and 0.140 L/kg in patients with heart failure.

Elimination Route

Following oral administration, furosemide is absorbed from the gastrointestinal tract. It displays variable bioavailability from oral dosage forms, ranging from 10 to 90%. The oral bioavailability of furosemide from oral tablets or oral solution is about 64% and 60%, respectively, of that from an intravenous injection of the drug.

Half Life

The half-life from the dose of 40 mg furosemide was 4 hours following oral administration and 4.5 hours following intravenous administration. The terminal half-life of furosemide is approximately 2 hours following parenteral administration. The terminal half-life may be increased up to 24 hours in patients with severe renal failure.

Clearance

Following intravenous administration of 400 mg furosemide, the plasma clearance was 1.23 mL/kg/min in patients with heart failure and 2.34 mL/kg/min in healthy subjects, respectively.

Elimination Route

The kidneys are responsible for 85% of total furosemide total clearance, where about 43% of the drug undergoes renal excretion. Significantly more furosemide is excreted in urine following the I.V. injection than after the tablet or oral solution. Approximately 50% of the furosemide load is excreted unchanged in urine, and the rest is metabolized into glucuronide in the kidney.

Pregnancy & Breastfeeding use

Pregnancy Category C. Frusemide should be cautiously used in cardiogenic shock complicated by pulmonary oedema and in the first trimester of pregnancy. Blood pressure and pulse during rapid diuresis should be monitored. Caution should be observed in patients liable to electrolyte deficiency. In case of nursing mother, Frusemide may inhibit lactation because it may pass into breast milk. In that case it should be used with caution.

Contraindication

Furosemide is contraindicated in anuria, electrolyte deficiency and pre-comatose states associated with liver cirrhosis. Hypersensitivity to furosemide or sulphonamides.

Acute Overdose

Symptoms: Dehydration, electrolyte disturbances, hypotension and cardiac toxicity, hypochloremic alkalosis, hypokalaemia, blood volume reduction. 

Management: Symptomatic and supportive treatment. Replacement of excessive fluid and electrolyte losses. Ensure adequate drainage in patients with urinary bladder outlet obstruction (e.g. prostatic hypertrophy). Treat hypotension with appropriate IV fluids.

Storage Condition

Store between 15-30°C. Protect from light.

Innovators Monograph

You find simplified version here Furosemide

FAQ

What is Furosemide used for?

Furosemide is used to reduce extra fluid in the body (edema) caused by conditions such as heart failure, liver disease, and kidney disease. This can lessen symptoms such as shortness of breath and swelling in your arms, legs, and abdomen. Furosemide is also used to treat high blood pressure.


How safe is Furosemide?

Furosemide is safe to take for a long time, but you will have to see your doctor or nurse every so often for blood and urine tests. These make sure the chemicals in your blood are properly balanced.

How does Furosemide work?

Furosemide works by helping your body get rid of excess salt and water. It does this by increasing the amount of urine your body makes. This helps lower your blood pressure as well as reduce swelling.

What are the common side effects of Furosemide?

Common side effects of Furosemide are include:

  • peeing more than normal, most people need to pee a couple of times within a few hours of taking furosemide - you may also lose a bit of weight as your body loses water.
  • feeling thirsty with a dry mouth.
  • headaches.
  • feeling confused or dizzy.
  • muscle cramps, or weak muscles.

Is Furosemide safe during pregnancy?

Furosemide should be used with caution during pregnancy, and only if the expected benefit to the mother is greater than any possible risk to the developing baby. It should not be used to treat pregnancy-induced high blood pressure.

Is Furosemide safe during breastfeeding?

Furosemide may pass into breast milk in small amounts and may also reduce the production of breast milk. It should be used with caution in women who are breastfeeding and only if the benefits outweigh any risks to the nursing infant.

Can I drink alcohol with Furosemide?

Furosemide does not directly interact with alcohol. However, it is best to avoid alcohol in the first few days of taking Furosemide, until you know how it affects you. Dizziness and light-headiness are common side effects of furosemide, which may be made worse with alcohol

Can I drive after taking Furosemide?

Don't drive if you feel dizziness after taking Furosemide.

What is the best time to take Furosemide?

Furosemide is best taken in the morning.

How many time can I take Furosemide daily?

It's usual to take Furosemide once a day in the morning.

How much Furosemide can I take in a day?

The usual dose in adults to treat high blood pressure is 20mg to 80mg a day. The usual dose in adults to treat heart failure or oedema (fluid build up in the body) is 20mg to 120mg a day.

How long does Furosemide take to work?

Furosemide starts to work within an hour after you take it. And it takes about 2 hours for half of a dose of the drug to leave your body.

How quickly does Furosemide act?

The onset of action after oral administration is within one hour, and the diuresis lasts about 6-8 hours. The onset of action after injection is five minutes and the duration of diuresis is two hours.

How long does Furosemide stay in my system?

Furosemide stays in your system and continues to work for about 6 to 8 hours after you take it. If you have kidney disease, the drug may stay in your body longer than usual.

Can I take Furosemide for a long time?

Furosemide is safe to take for a long time, but you will have to see your doctor or nurse every so often for blood and urine tests. These make sure the chemicals in your blood are properly balanced.

How long can I take Furosemide?

A dose of Furosemide works for about 6 hours. Depending on the reason why you're on Furosemide, you may have to take it for a long time, even for the rest of your life.

What happens if I miss a dose?

Furosemide is sometimes used only once, so you may not be on a dosing schedule. If you are using the medication regularly, take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention. Overdose symptoms may include feeling very thirsty or hot, heavy sweating, hot and dry skin, extreme weakness, or fainting.

Is Furosemide bad for my kidneys?

Water pills like hydrochlorothiazide and Furosemide, used for high blood pressure and edema, can cause dehydration and can also lead to swelling and inflammation of the kidneys.

Who should not take Furosemide?

You should not use Furosemide if you are unable to urinate. If you're ill with a fever, sweats and shaking, being sick (vomiting) or have severe diarrhoea, contact your doctor as you may need to stop taking Furosemide for 1 to 2 days until you are better.

Can Furosemide affects my liver?

Furosemide can cause very low electrolyte levels, which can cause serious liver damage and loss of brain function. (Electrolytes are minerals that help control the fluid balance in your body and help with other important functions.) Your doctor will monitor you closely.

Can Furosemide affect my heart?

If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks.

What happen If I stop taking Furosemide ?

Talk to your doctor if you want to stop taking Furosemide. Stopping it may cause your blood pressure to rise - and this may increase your risk of heart attack and stroke. If you're bothered by side effects, your doctor may be able to prescribe you a different medicine.

*** Taking medicines without doctor's advice can cause long-term problems.
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