Lasix (Furosemide)

(℞) Prescription Required

    Lasix (Furosemide) Dosage and Side Effects

    LASIX is a prescription drug used to eliminate extra water and salt in people who have problems with fluid retention. Swelling and fluid retention , also known as edema, can be caused by congestive heart failure, liver or kidney disease, as well as other conditions. LASIX is also used on its own or together with other drugs to treat high blood pressure (hypertension).

    Warnings and Precautions

    Elderly patients taking LASIX are more likely to have age-related liver, kidney, or heart problems.

    Before taking LASIX, talk to your doctor about whether you might be allergic to it as well as whether you have other allergies, especially those involving sulfa drugs:

    • Sulfamethoxazole (Bactrim, Septra)
    • Sulfasalazine (Azulfidine)
    • Sulfisoxazole (Gantrisin)
    • Erythromycin Sulfisoxazole (Pediazole)

    Tell your doctor if you change your exercise routine and diet, quit smoking, or reduce stress. These changes may require your doctor to reevaluate your dosage.

    While using LASIX, your doctor should conduct periodic tests on your kidneys and blood mineral levels to monitor your progress or check for side effects. It's also important to check your blood pressure regularly while on LASIX, so ask your doctor how you can do so at home.

    If you are diabetic, LASIX might affect your blood sugar levels so they will need to be monitored and reported to your doctor. Your diabetes medication or diet might also need to be adjusted.

    If you experience prolonged diarrhea or vomiting be sure to let your doctor know since this can lead to dehydration.

    Be sure to give your doctor a complete medical history to help him/her decide if this drug is right for you. Tell your physician if you have any of the following conditions:

    • Difficulty urinating
    • Kidney problems
    • Liver problems
    • Diabetes
    • Gout
    • Lupus
    • Anemia
    • Hearing problems
    • High levels of uric acid
    • Low levels of calcium, chlorine, potassium, magnesium, or sodium in your blood
    • Low blood pressure or low blood volume
    • Low protein in the blood due to a kidney problem or radiocontrast nephropathy, a kidney condition that could worsen your side effects

    Pregnancy and LASIX (Furosemide)

    It's still unclear how LASIX might affect your unborn child. If you plan to breastfeed, you should be aware that LASIX passes into your breast milk. Let your doctor know right away if you are pregnant, plan to become pregnant, or are breastfeeding.

    Side Effects

    Call your doctor right away if you notice any of these side effects.

    • Allergic reaction: itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
    • Blistering, peeling, red skin rash
    • Chest pain, shortness of breath
    • Confusion, weakness, muscle twitching
    • Dry mouth, increased thirst, muscle cramps, nausea or vomiting, uneven heartbeat
    • Sudden and severe stomach pain, nausea, vomiting, fever, lightheadedness
    • Hearing loss, ringing in the ears
    • Lightheadedness, dizziness, fainting
    • Severe diarrhea
    • Unusual bleeding or bruising
    • Yellow skin or eyes

    If you have these less serious side effects, talk with your doctor:

    • Loss of appetite
    • Stomach cramps

    Those who use LASIX have also reported ringing in the ears, having a hard time hearing or deafness, especially in cases where they had severe kidney disease, were taking a higher dose than prescribed, or were using LASIX together with certain medicines.

    LASIX could also result in severe dehydration.

    Stop taking LASIX and contact your doctor right away if you have the following:

    • Muscle cramps
    • Weakness
    • Unusual tiredness
    • Confusion
    • Severe dizziness
    • Fainting
    • Drowsiness
    • Unusual dry mouth/thirst
    • Nausea
    • Vomiting
    • Fast/irregular heartbeat
    • Unusual decrease in the amount of urine your body is producing
    • Numbness
    • Tingling
    • Pain
    • Swelling of the arms and legs
    • Hearing changes
    • Stomach pain
    • Yellowing of the eyes or skin

    Get emergency medical help right away if you experience an allergic reaction. Signs of a problem might include difficulty breathing, swelling of your face, lips, tongue, or throat as well as hives.

    Interactions with this medication

    Give your doctor a complete list of all the medications you are using, including over-the-counter (OTC) items like vitamins and herbal products. Some medications might interact with LASIX, increasing the side effects or decreasing its effectiveness.

    Check with your doctor before using LASIX with the following medications:

    • Aspirin
    • Antibiotics like cephalexin (Keflex) or neomycin (Neo-Fradin)
    • Blood pressure or heart medications, such as lisinopril (Prinivil or Zestril)
    • Valsartan (Diovan)
    • Chloral hydrate (Noctec)
    • Cisplatin (Platinol or Platinol-AQ)
    • Cyclosporine (Sandimmune, Neoral or Gengraf)
    • Ethacrynic acid (Edecrin)
    • Lithium (Eskalith or Lithobid)
    • Methotrexate (Trexall)
    • Non-steroidal anti-inflammatory drugs (NSAIDs) such as indomethacin (Indocin) Norepinephrine (Levophed)
    • Phenytoin (Phenytek, Dilantin or Dilantin-125)
    • Succinylcholine (Anectine or Quelicin)
    • Sucralfate (Carafate)
    • Tubocurarine (Tubarine)

    If you take aminoglycoside (Gentamicin/Tobramycin) this could affect your hearing.

    LASIX (Furosemide) and Other Interactions

    LASIX might reduce the potassium levels in your blood, so you should have your potassium blood levels watched closely by your doctor. Potassium supplements may be prescribed if needed.

    This medicine is also known to make you more sensitive to the sun, so try to avoid long-term exposure to the sun, along with tanning booths and sunlamps. Make sure to wear sunscreen and protective clothing when you go out.

    Since LASIX might make you dizzy or cause blurred vision, it's important that you avoid driving, using machinery, or partaking in any activity that requires you to be alert or have clear vision until you know how the medicine affects you.

    You should also limit your intake of alcoholic beverages while on LASIX.

    If you suffer from high blood pressure, don't use over-the-counter appetite suppressants or cold medicines, which might impact your blood pressure.

    To avoid dehydration, drink plenty of fluids while taking LASIX (unless your doctor has limited your fluid intake).

    Proper Use of this medication

    Your doctor will decide what dose you should take based on your condition and medical history. Never stop taking LASIX or alter your dose without your doctor's approval.

    Adults who have fluid retention problems will typically begin with a single dose of 20 milligrams (mg) to 80 mg. The dose in children will vary based on what your doctor deems appropriate.

    Adults who have high blood pressure often begin with 40 mg, twice per day. The dosage may be adjusted for elderly patients.

    In the event you are using sucralfate (Carafate), cholestyramine (Questran or Prevalite), and colestipol (Colestid), you should take these medicines at least two hours before you take LASIX.

    Let your doctor know right away if your condition doesn't improve or worsens.

    LASIX (Furosemide) Overdose

    If you think you might have taken too much, get to the emergency room right away or call a poison control center. Signs of an overdose range from fainting and severe weakness to a severe decrease in the amount of urine your body is producing.

    Missed Dose of LASIX (Furosemide)

    If you forget to take your medication, take it as soon as you remember unless it's near the time of your next dose. If that is the case, skip the missed dose and resume your regular schedule. Never “double up” and take more than one dose at a time.

    Other related products

    The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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