Lasix (furosemide)

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Brand Name

Lasix {Sanofi-Aventis}

Generic Name

furosemide, pronounced fur OH se mide

What is Lasix?

Lasix is a loop diuretic that causes increased urine flow. Lasix may be used to treat edema caused by congestive heart failure, liver disease, or a kidney disorder like nephrotic syndrome. Patients with hypertension may also be prescribed Lasix. Lasix may also be used for purposes not indicated in this medication guide.


Key Facts About Lasix

Lasix is known as a loop diuretic, or a water pill. Lasix can help you if you have edema and swelling by preventing your body from absorbing too much salt, which subsequently allows the salt to be passed in your urine.

If you are not able to urinate you should not use Lasix.

You should never take more Lasix than your doctor recommends because high doses of Lasix can lead to irreversible hearing loss.

Be careful about becoming dehydrated, as Lasix will cause you to urinate more often than usual. Your doctor will tell you how to be sure that you get enough salt and potassium in your diet, and if you should take potassium supplements.

Lasix is in FDA pregnancy category C. We do not know if Lasix will harm an unborn baby. You should tell your doctor if you are pregnant or plan to become pregnant while taking Lasix. We do know that Lasix can pass into breast milk and may harm a nursing baby, so you should not breast-feed while taking Lasix.


Before You Take Lasix

If you are allergic tofurosemide or to sulfa drugs you should not take Lasix.

Let your doctor know if you tell your doctor if you have recently had a magnetic resonance imaging) (MRI) or any type of scan which uses a radioactive dye that is injected into your veins before taking Lasix.

If you have kidney disease, an enlarged prostate, urination problems, cirrhosis or other liver disease, or an electrolyte imbalance you should tell your doctor before taking Lasix.

Tell your doctor before starting treatment with Lasix if you have high cholesterol, gout, lupus, diabetes, or a bladder obstruction.

While you are taking Lasix you should be careful about getting up too quickly from a sitting or lying position, as you may experience dizziness. Be sure to get up slowly and steady yourself to prevent falling.

Ask your doctor for instructions on how you can avoid becoming dehydrated. Follow your doctor’s instructions exactly as to the type and amount of liquids you should drink while you are taking Lasix.

If you regularly are exposed to tanning beds or sunlight be aware that Lasix can make you sunburn more easily. You should wear protective clothing and use sunscreen, an SPF 30 or higher
when you are outdoors and avoid tanning beds.

If you take sucralfate (Carafate) you must wait at least 2 hours before or after to take Lasix.


Lasix Drug Interactions

You should inform your doctor if you are taking any of the following:

  • antibiotics like such as amikacin (Amikin), cefdinir (Omnicef), cefprozil (Cefzil), cefuroxime (Ceftin), cephalexin (Keflex), gentamicin (Garamycin), kanamycin (Kantrex), neomycin (Mycifradin, Neo Fradin, Neo Tab), paromomycin (Humatin, Paromycin), streptomycin, and tobramycin (Nebcin, Tobi)
  • cancer medicine (chemotherapy)
  • cold medicine
  • cyclosporine (Neoral, Gengraf, Sandimmune)
  • diet pills
  • digoxin (Lanoxin)
  • ethacrynic acid (Edecrin)
  • heart or blood pressure medications like benazepril (Lotensin), candesartan (Atacand), eprosartan (Teveten), enalapril (Vasotec), irbesartan (Avapro, Avalide), lisinopril (Prinivil, Zestril), losartan (Cozaar, Hyzaar), olmesartan (Benicar), quinapril (Accupril), ramipril (Altace), telmisartan (Micardis) and valsartan (Diovan)
  • indomethacin (Indocin)
  • laxatives (Metamucil, Milk of Magnesia, Colace, Dulcolax, Epsom salts, and senna)
  • lithium (Eskalith, Lithobid)
  • methotrexate (Rheumatrex, Trexall)
  • phenytoin (Dilantin)
  • salicylates like aspirin, Disalcid, Doan’s Pills, Dolobid, Salfle and Tricosal
  • steroids (prednisone)

Other drugs you take that are not listed may interact with Lasix. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Lasix

You should take Lasix exactly as prescribed by your doctor. Do not take Lasix in larger or smaller amounts, or for shorter or longer than recommended. Follow the directions on your prescription label.

If you are taking Lasix Oral Suspension you should use the proper measuring device, such as a special dose-measuring spoon or medicine cup. Do not use a regular kitchen table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Your doctor may want to have your blood tested often if you take Lasix long-term.

Lasix needs to be stored at room temperature, and away from light, moisture and heat.

If you are taking Lasix liquid you should use your opened bottle within 60 to 90 days after opening it. If you are not sure about how many days your medicine is good for, you can ask your pharmacist. Be sure to throw away any unused liquid after that time has passed.

Lasix is occasionallyused only once, so you may not be on a dosing schedule. If you are using the medication regularly, and miss a dose you should take the missed dose as soon as you remember. You should skip the missed dose if it is almost time for your next scheduled dose. Never take extra medicine to make up the missed dose.


Lasix Side Effects

If you experience any of the following adverse effects you should stop taking Lasix and seek emergency medical help immediately:

  • allergic reactions such as breathing difficulties, hives or swelling of your face, lips , throat or tongue
  • body aches
  • clay colored stools
  • chest pain
  • confusion
  • cough that is new or worsening with fever
  • dry mouth with increased thirst
  • ear ringing and hearing loss
  • easy bleeding or bruising
  • fainting
  • feeling very thirsty or hot
  • fever
  • flu symptoms
  • headache
  • heavy sweating,
  • hot and dry skin
  • irregular heartbeat
  • jaundice
  • light headed felling
  • loss of appetite
  • muscle pain and weakness
  • nausea
  • numbness which is sudden
  • overactive reflexes
  • painful or difficult urination
  • paleness
  • purple or red pinpoint spots under your skin
  • seizures
  • severe skin reaction which included fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads, especially in your face and upper body and causes blistering and peeling
  • severe tingling pain
  • shallow or stopped breathing
  • short of breath with rapid heart rate
  • skin rash
  • swelling with rapid weight gain
  • swollen glands
  • trouble breathing
  • trouble concentrating
  • unsteady feeling
  • unusual bleeding, like from your nose, mouth, rectum or vagina
  • upper stomach pain
  • urinating less than usual or not at all, or in an increased amount
  • urine that is dark
  • vomiting
  • weakness

Less serious Lasix side effects may include:

  • blurred vision
  • constipation
  • diarrhea
  • dizziness
  • rash that is mild and itchy
  • spinning sensation
  • stomach pain

It should be noted that this is not a complete list of possible side effects of Lasix. You should contact your physician for a complete list and medical advice regarding these effects.


Lasix Description and Dosing

Lasix is available in tablets in dosages of 20mg, which are white, oval and imprinted with “Lasix” on one side. Tablets in 40mg are also available, which are supplied as white, round, monogrammed, scored and are imprinted with “Lasix 40” on one side. There is also an 80mg tablet dose of Lasix, which is white, round, monogrammed, faceted edged, and imprinted with “Lasix 80” on one side.

The typical initial dose of Lasix is between 20mg and 80mg, once daily. Your doctor will tell you what the appropriate dose of Lasix is for you. Do not attempt to alter or change your dose without your physician’s consent.

If you suspect that you have overdosed with Lasix you should seek emergency help immediately.


Ingredients in Lasix

The primary active ingredient in Lasix is furosemide. Inactive ingredients include lactose monohydrate NF, magnesium stearate NF, starch NF, talc USP, and colloidal silicon dioxide NF.

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

The use of the information in this guide is at your sole risk. This information is provided "AS IS" with no warranties to accuracy or timeliness.

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