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Furosemide oral

Updated 2 Feb 2023 | Loop diuretics


Low strength oral formulations of furosemide

Drugs List

  • FRUSOL 20mg/5ml oral solution sugar-free
  • FRUSOL 40mg/5ml oral solution sugar-free
  • FRUSOL 50mg/5ml oral solution sugar-free
  • furosemide 20mg tablets
  • furosemide 20mg/5ml oral solution sugar-free
  • furosemide 40mg tablets
  • furosemide 40mg/5ml oral solution sugar-free
  • furosemide 50mg/5ml oral solution sugar-free
  • Therapeutic Indications



    All conditions requiring prompt diuresis including:
    Oedema of cardiac, pulmonary, hepatic or renal (including nephrotic syndrome) origin,
    Peripheral oedema of mechanical obstruction or venous insufficiency.

    Maintenance therapy of mild oedema of any origin.




    Initial dose: 40mg in the morning.
    Maintenance dose: 20mg or 40mg on alternate days. This dose may be increased to 120mg daily in the case of resistant oedema. Higher doses may be used.

    20mg to 40mg twice daily, titrated to response.
    If no clinical response is seen at the higher dose, it is advisable to consider the addition of other hypertensive agents, rather than an increase in furosemide dosage.


    As furosemide is eliminated more slowly in elderly patients the dose should be titrated to the minimum effective dose.


    Children aged 12 years and over
    (See Dosage; Adult)

    Children aged under 12 years
    1mg/kg to 3mg/kg daily.
    Maximum daily dose: 40mg.

    The following dosing regimes may be suitable:

    Pulmonary oedema; Oedema in heart failure, renal disease, and hepatic disease
    Children aged 12 to 18 years
    20mg to 40mg daily. Increase in resistant oedema to 80mg to 120mg daily.
    Children aged 1 month to 12 years
    0.5mg/kg to 2mg/kg given two or three times a day (or given once a day if postmenstrual age under 31 weeks). Higher doses may be required in resistant oedema.
    Maximum daily dose: 12mg/kg or 80mg total.

    Oliguria (unlicensed)
    Children aged 12 to 18 years
    Initial dose: 250mg daily.
    Increase dose, if necessary, in steps of 250mg given every 4 to 6 hours.
    Maximum dose: 2g.

    Tablets can be crushed and mixed with water or injection solution diluted and given by mouth.


    Pulmonary oedema; Oedema in heart failure, renal disease, and hepatic disease
    0.5mg/kg to 2 mg/kg given one or two times a day (or given once a day if postmenstrual age under 31 weeks).

    Tablets can be crushed and mixed with water or injection solution diluted and given by mouth.

    Additional Dosage Information

    Diuresis lasts for approximately 4 hours following administration so the dosing regime can be adjusted to suit the patient's requirements.


    Cardiac glycoside toxicity
    Addison's disease
    Hepatic coma
    Hepatic encephalopathy
    Hereditary fructose intolerance
    Long QT syndrome
    Pre-coma associated with hepatic cirrhosis
    Renal damage secondary to nephrotoxic agents
    Renal impairment secondary to hepatotoxic agents
    Severe hypokalaemia
    Severe hyponatraemia
    Torsade de pointes

    Precautions and Warnings

    Family history of long QT syndrome
    Predisposition to hypotension
    Premature infants
    Adrenal disorder
    Benign prostatic hyperplasia
    Diabetes mellitus
    Electrolyte imbalance
    Glucose-galactose malabsorption syndrome
    Hepatic impairment
    Hepato-renal syndrome
    History of gout
    History of torsade de pointes
    Lactose intolerance
    Metabolic alkalosis
    Renal impairment
    Urinary obstruction

    Correct electrolyte disorders before treatment
    Correct hypotension before initiating treatment
    May decrease glucose tolerance in patients with diabetes mellitus
    Advise ability to drive/operate machinery may be affected by side effects
    Correct hypovolaemia prior to administration
    Not all available products are licensed for all age groups
    Oral solution contains alcohol
    Oral solution with maltitol unsuitable in hereditary fructose intolerance
    Some brands contain Quinoline Yellow (E104) : May cause allergic reactions
    Some formulations contain lactose
    Consider monitoring ECG in patients at risk of QT prolongation
    Monitor blood / urinary glucose concentrations in diabetic patients
    Monitor blood / urinary glucose in patients suspected of latent diabetes
    Monitor creatinine, blood urea nitrogen (BUN) and urinary output
    Monitor fluid and electrolyte status
    Monitor for signs of blood dyscrasias eg fever, sore throat, malaise etc
    Monitor hepatic function
    Monitor patients at risk of gout
    Monitor serum potassium regularly
    Premature infants: perform renal ultrasonography and monitor renal function
    Excess consumption of liquorice may increase the risk of hypokalaemia
    May precipitate gout
    Potassium supplements may be required
    Discontinue treatment before glucose tolerance test
    Discontinue if blood dyscrasia develops
    Discontinue if evidence of significant bone marrow depression
    Advise patient not to take NSAIDs unless advised by clinician

    Profound diuresis may occur resulting in fluid and electrolyte depletion (sodium, potassium, chloride and bicarbonate). These deficiencies must be corrected or the treatment withdrawn. During long-term or high dose therapy potassium supplements may be necessary.

    Serum cholesterol and triglyceride levels may increase during treatment but should return to normal within 6 months of discontinuation.

    Pregnancy and Lactation


    Use furosemide with caution in pregnancy.

    Furosemide has been given after the first trimester of pregnancy without causing foetal or newborn adverse effects. It should only be given during pregnancy if strictly indicated and for short-term treatment.

    Schaefer (2007) states that diuretics are no longer part of the standard therapy for hypertension and oedema during pregnancy. They should only be used for particular indications. Furosemide can be given when treatment of heart or renal failure requires a diuretic.

    A study between 1985 and 1992 showed that out of 350 neonates exposed to furosemide in the first trimester, 18 had major birth defects (such as cardiovascular defects and limb reduction defects) (Briggs, 2011).

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Furosemide is contraindicated in breastfeeding.

    Furosemide should be discontinued during furosemide treatment as the drug may inhibit lactation and is secreted into the breast milk.

    An alternative drug may be preferred especially whilst nursing a newborn or premature infant.

    Hale (2010) states that it unlikely that the amount of furosemide transferred into breast milk would produce any effects in a nursing infant.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    Acute renal failure
    Aggravation of metabolic alkalosis
    Anaphylactic reaction
    Anaphylactoid reaction
    Aplastic anaemia
    Blood urea increased
    Blurred vision
    Bone marrow depression
    Decrease in plasma calcium
    Decreased glucose tolerance
    Delayed reactions
    Dry mouth
    Erythema multiforme
    Exfoliative dermatitis
    Haemolytic anaemia
    Hearing loss (reversible)
    Hepatic encephalopathy
    Impaired concentration
    Increase in plasma triglyceride concentration
    Increase in serum cholesterol (transient)
    Increase in serum transaminases
    Increased thirst
    Interstitial nephritis
    Intrahepatic cholestasis
    Metabolic alkalosis
    Muscle cramps
    Muscle weakness
    Orthostatic dysregulation
    Precipitation of diabetes
    Psychiatric disorders
    Sensation of pressure
    Serum creatinine increased
    Severe bullous lesions
    Toxic epidermal necrolysis
    Urinary retention
    Visual disturbances
    Yellow vision


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: January 2014

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

    Medications and Mothers' Milk, 14th Edition (2010) Hale, T. Hale Publishing, Amarillo, Texas.

    Summary of Product Characteristics: Frusol 20mg/5ml Oral solution. Rosemont Pharmaceuticals Ltd. Revised July 2013.

    Summary of Product Characteristics: Frusol 40mg/5ml Oral solution. Rosemont Pharmaceuticals Ltd. Revised July 2013.

    Summary of Product Characteristics: Frusol 50mg/5ml Oral solution. Rosemont Pharmaceuticals Ltd. Revised July 2013.

    Summary of Product Characteristics: Furosemide 40mg Tablets. Accord Healthcare Ltd. Revised July 2013.

    Summary of Product Characteristics: Furosemide 20mg Tablets BP. Actavis UK Ltd. Revised May 2013.

    Summary of Product Characteristics: Furosemide 40mg Tablets BP. Actavis UK Ltd. Revised May 2013.

    Summary of Product Characteristics: Furosemide tablets 40mg. Amdipharm Mercury Company Ltd. Revised February 2013.

    NICE Evidence Services Available at: Last accessed: 24 August 2017

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Furosemide Last revised: September 7, 2013
    Last accessed: January 9, 2014

    The Drug Database for Acute Porphyria (NAPOS).
    Available at:
    Furosemide Last revised: September 22, 2009
    Last accessed: January 9, 2014

    The Welsh Medicines Information Centre (WMIC).
    Available at:
    Furosemide Last revised: September, 2013
    Last accessed: January 9, 2014

    European porphyria network.
    Available at:
    Last accessed: January 9, 2014

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