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Furosemide Patient Tips

Medically reviewed on Sep 14, 2017 by C. Fookes, BPharm.

How it works

  • Furosemide significantly increases urination by inhibiting the reabsorption of salts in the kidneys. It may be used to treat excessive fluid retention.
  • Furosemide belongs to the class of medicines known as loop diuretics. It is a potent loop diuretic.


  • Used to relieve the body of excess fluid caused by heart failure, kidney failure, cirrhosis of the liver and other conditions.
  • May be used in addition to other medicines for the treatment of high blood pressure.
  • Available as an injectable form.
  • Generic furosemide is available.


If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Dizziness on standing, gastrointestinal disturbances, changes in blood counts, and alterations in cholesterol levels or liver function.
  • Furosemide's effect is very strong. Can lead to a significant depletion of electrolytes which may lead to side effects such as muscle cramps and an irregular heart beat; risk is greater in people with a restricted salt intake or on certain medications.
  • Tinnitus and reversible or irreversible hearing impairment have been reported. The risk is greater with higher dosages, injectable furosemide, severe renal impairment, low protein levels, and concomitant therapy with other drugs that are also toxic to the ears.
  • May increase blood glucose levels and affect laboratory test results.
  • Older people may not respond as well to the initial diuretic effect of furosemide.
  • May not be suitable for some people including those with cirrhosis of the liver or ascites, kidney disease, already electrolyte depleted or dehydrated.
  • May interact with a number of other drugs including those that also lower blood pressure or potassium, lithium, corticosteroids, digoxin, phenytoin and methotrexate.

Notes: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. For a complete list of all side effects, click here.

Bottom Line

Furosemide increases urination which relieves excess fluid but may also lead to depletion of certain electrolytes in the body (such as potassium)


  • Dosages may need to be adjusted depending on the individual; higher dosages need extra monitoring by a doctor. Some individuals may only need furosemide two to four times per week.
  • You may be more sensitive to sunlight while taking furosemide; use an SPF 30-50+ sunblock when outside.
  • Tell your doctor if you develop diarrhea or vomiting while taking furosemide.
  • Get up slowly when going from a lying down or sitting position to standing.
  • Your electrolyte levels will need monitoring regularly including occasional testing for diabetes.
  • Potassium supplements or extra dietary potassium may be needed to counteract the effects of low potassium caused by furosemide.
  • If you have diabetes, be aware that furosemide may increase your blood glucose levels.

Response and Effectiveness

  • The onset of diuresis (increased urination) is within an hour. The peak effects of furosemide are seen within one to two hours and its effects last for 6 to 8 hours.
  • Furosemide is very potent. Excessive amounts can lead to profound urination and water and electrolyte loss. Severe dehydration may result.


Furosemide [Package Insert] Revised 07/2017. West-Ward Pharmaceuticals Corp.

  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use furosemide only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that this information is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This drug information does not endorse drugs, diagnose patients or recommend therapy. It is an informational resource designed as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of this information. 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.

Copyright 1996-2017 Revision Date: 2017-09-14 21:26:47