Generic Name: Furosemide

  • What is this medication and its most common uses?

    Lasix is a medicine used to treat fluid retention associated with heart failure and liver or kidney disease. Lasix is also used alone or in combination with other medicines to treat high blood pressure.

  • What should I know when beginning and continuing on this medication?

    How does this medication work?

    Lasix is a water pill and works by eliminating extra fluid and sodium (salt) from your body, thereby reducing swelling and lowering your blood pressure.

    What are the beneficial effects of this medication and when should I begin to have results?

    What: By lowering your blood pressure, Lasix may lower your risk of a stroke or a heart attack.

    When: Lasix may start eliminating extra fluid and sodium from your body within a few hours of taking it. Though you may not feel an improvement or change in the way you feel, it is very important to keep taking your medicine as prescribed to keep your condition under control.

    How do I know it is working?

    You may notice an improvement in your swelling and/or decrease in your blood pressure after you start taking Lasix. Check your blood pressure regularly. Your healthcare provider will also check your blood pressure at every visit. Following an appropriate diet and exercise plan will also affect your blood pressure results.

  • What are the possible side effects of this medication?

    The following is not a full list of side effects. Side effects cannot be anticipated. If any develop or change in intensity, tell your healthcare provider as soon as possible. Only your healthcare provider can determine if it is safe for you to continue taking this medication.

    Lasix is a strong water pill which, if taken in doses higher than prescribed by your healthcare provider, can lead to significant water and electrolyte (chemicals that are important for the cells in your body to function, such as sodium and potassium) loss. Therefore, it is very important that you take Lasix exactly as prescribed by your healthcare provider.

    More common side effects may include: yellowing of your skin or the whites of your eyes, loss of appetite, tingling or numbness of your hands or feet, diarrhea, nausea, vomiting, dizziness, rash, increased sensitivity of your skin to sunlight, fever, restlessness.

    Less common side effects may include:

    Changes in electrolytes with symptoms such as dry mouth, thirst, weakness, tiredness, drowsiness, restlessness, muscle pains or cramps, muscle tiredness, dizziness or fainting, low or no urine output, fast heartbeat, or nausea and vomiting.

    Hearing problems with symptoms such as ringing in your ears, difficulty hearing, or deafness, especially if you have severe kidney disease, take a higher dose than prescribed by your healthcare provider, or if you take Lasix with certain other medicines.

  • Who should not take this medication?

    Do not take Lasix if you are allergic to it or any of its ingredients.

    Do not take Lasix if you are unable to produce urine.

  • What should I tell my healthcare provider before I take the first dose of this medication?

    Tell your healthcare provider about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Lasix. Also, talk to your healthcare provider about your complete medical history, especially if you have diabetes; gout (severe and painful inflammation of the joints); lupus (a disease that affects the immune system); problems emptying your bladder, such as an enlarged prostate or narrowing of the urethra (the tube that connects from the bladder to the genitals to lead urine out of your body); or if you are allergic to sulfonamide medications (such as sulfamethoxazole or sulfisoxazole).

  • What is the usual dosage?

    The information below is based on the dosage guidelines your healthcare provider uses. Depending on your condition and medical history, your healthcare provider may prescribe a different regimen. Do not change the dosage or stop taking your medication without your healthcare provider's approval.

    Fluid Retention

    Adults: The usual starting dose is 20 to 80 milligrams (mg) given as a single dose. Your healthcare provider may give you additional doses as needed, until the desired effect is achieved.

    Children: Your healthcare provider will prescribe the appropriate dose for your child, based on his/her weight.

    High Blood Pressure

    Adults: The usual starting dose is 40 mg twice a day. If you are elderly, your healthcare provider may adjust your dose appropriately.

  • How should I take this medication?

    Take Lasix exactly as prescribed by your healthcare provider. Do not change your dose or stop taking Lasix without first talking to your healthcare provider.

    If you are also taking a medicine called sucralfate, take it at least 2 hours before or after you take Lasix.

  • What should I avoid while taking this medication?

    If you have high blood pressure, do not take any medicines that can increase your blood pressure (such as over-the-counter appetite suppressants or cold medicines).

    Do not become dehydrated. Drink plenty of fluids while you are taking Lasix.

  • What are the possible food and drug interactions associated with this medication?

    If Lasix is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your healthcare provider before combining Lasix with the following: aspirin, certain antibiotics (such as cephalexin or neomycin), certain blood pressure/heart medications (such as lisinopril or valsartan), chloral hydrate, cisplatin, cyclosporine, ethacrynic acid, lithium, methotrexate, nonsteroidal anti-inflammatory drugs (NSAIDs) (such as indomethacin), norepinephrine, phenytoin, succinylcholine, sucralfate, or tubocurarine.

  • May I receive this medication if I am pregnant or breastfeeding?

    The effects of Lasix during pregnancy are unknown. Lasix can be found in your breast milk if you take it while breastfeeding. Tell your healthcare provider immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of this medication?

    If you miss a dose of Lasix, take it as soon as you remember. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store this medication?

    Store at room temperature.

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