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Furosemide - Oral

Pronunciation: fyou-ROW-seh-mide

Common Brand Name(s): Lasix

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Warning

Furosemide is a very potent medication. Using too much of this drug can lead to serious water and salt/mineral loss. It is important that you are closely monitored by your doctor while taking this medication. Tell your doctor right away if you become very thirsty or confused, or develop muscle cramps/weakness. See also Side Effects section.

Uses

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.

This drug is also used to treat high blood pressure. Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems.

Furosemide is a "water pill" (diuretic) that causes you to make more urine. This helps your body get rid of extra water and salt.

How To Use

Read the Patient Information Leaflet if available from your pharmacist before you start taking furosemide and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually once or twice daily. It is best to avoid taking this medication within 4 hours of your bedtime to prevent having to get up to urinate.

The dosage is based on your medical condition, age, and response to treatment. For children, the dose is also based on weight. Older adults usually start with a lower dose to decrease the risk of side effects. Do not increase your dose or take it more often than directed.

Take this medication regularly in order to get the most benefit from it. To help you remember, take it at the same time(s) of the day as directed. Keep taking this medication even if you feel well. Most people with high blood pressure do not feel sick.

Sucralfate, cholestyramine, and colestipol can decrease the absorption of furosemide. If you are taking any of these drugs, separate the timing of each dose from furosemide by at least 2 hours.

Tell your doctor if your condition does not improve or if it worsens (for example, your blood pressure readings remain high or increase).

Side Effects

Dizziness, lightheadedness, headache, or blurred vision may occur as your body adjusts to the medication. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

This medication may cause dehydration and electrolyte imbalance. Tell your doctor right away if you have any symptoms of dehydration or electrolyte imbalance, including unusual dry mouth/thirst, muscle cramps/weakness, slow/fast/irregular heartbeat, or confusion.

Tell your doctor right away if you have any serious side effects, including:

  • signs of kidney problems (such as change in the amount of urine)
  • fainting
  • numbness/tingling/pain/redness/swelling of the arms/legs
  • hearing changes (such as ringing in the ears, temporary or permanent decreased hearing/deafness)
  • signs of liver problems (such as stomach/abdominal pain, yellowing eyes/skin)

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking furosemide, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

  • kidney problems
  • liver problems
  • inability to make urine
  • gout
  • lupus

If you have diabetes, furosemide may make it harder to control your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor.

Furosemide may reduce the potassium level in your blood. Your doctor may instruct you to add potassium-rich foods to your diet (such as bananas, orange juice) or prescribe potassium supplements to prevent potassium loss. Ask your doctor for more details.

This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness.

This drug may make you dizzy or blur your vision. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Severe sweating, diarrhea, or vomiting may cause dehydration and cause you to feel lightheaded. Tell your doctor if you have severe diarrhea or vomiting. To prevent dehydration, drink plenty of fluids unless your doctor tells you not to.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Babies born early (premature infants) and children may be more sensitive to certain effects of this drug, such as kidney stones.

Older adults may be more sensitive to the effects of this drug, especially dizziness and water/mineral loss.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This drug passes into breast milk and may affect milk production. Consult your doctor before breast-feeding.

Drug Interactions

See also the How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include:

  • desmopressin
  • ethacrynic acid
  • lithium

Some products have ingredients that could raise your blood pressure or worsen your swelling. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen).

This medication may interfere with certain lab tests (such as thyroid hormone levels), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: fainting, severe weakness, a severe decrease in the amount of urine.

Notes

Do not share this medication with others.

Lifestyle changes that may help this medication work better include exercising, stopping smoking, reducing stress, and changing your diet. Consult your doctor for more details.

Lab and/or medical tests (such as kidney function, blood mineral levels such as potassium) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

Check your blood pressure regularly while taking this medication. Learn how to monitor your own blood pressure at home, and share the results with your doctor.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.