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Generic Name: furosemide (fur OH se mide)
Brand Names: Lasix, Diaqua-2, Lo-Aqua

What is Lasix?

Lasix (furosemide) is a loop diuretic (water pill) that prevents your body from absorbing too much salt. This allows the salt to instead be passed in your urine.

Lasix is used to treat fluid retention (edema) in people with congestive heart failure, liver disease, or a kidney disorder such as nephrotic syndrome.

Lasix is also used to treat high blood pressure (hypertension).

Important information

You should not use Lasix if you are unable to urinate.

Do not take more Lasix than your recommended dose. High doses of furosemide may cause irreversible hearing loss.

Before using Lasix, tell your doctor if you have kidney disease, enlarged prostate, urination problems, cirrhosis or other liver disease, an electrolyte imbalance, high cholesterol, gout, lupus, diabetes, or an allergy to sulfa drugs.

Tell your doctor if you have recently had an MRI (magnetic resonance imaging) or any type of scan using a radioactive dye that is injected into your veins. Do not take more of this medication than is recommended. High doses of furosemide may cause irreversible hearing loss. If you are being treated for high blood pressure, keep using this medication even if you feel fine. High blood pressure often has no symptoms.

Before taking this medicine

You should not use Lasix if you are allergic to furosemide, or:

  • if you are unable to urinate.

To make sure Lasix is safe for you, tell your doctor if you have:

  • kidney disease;

  • enlarged prostate, bladder obstruction or other urination problems;

  • cirrhosiss or other liver disease;

  • an electrolyte imbalance (such as low levels of potassium or magnesium in your blood);

  • high cholesterol or triglycerides (a type of fat in the blood);

  • gout;

  • lupus;

  • diabetes; or

  • sulfa drug allergy.

Tell your doctor if you have an MRI (magnetic resonance imaging) or any type of scan using a radioactive dye that is injected into your veins. Both contrast dyes and furosemide can harm your kidneys.

It is not known whether Lasix will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medicine.

Furosemide can pass into breast milk and may harm a nursing baby. This medicine may also slow breast milk production. Tell your doctor if you are breast-feeding a baby.

How should I take Lasix?

Take Lasix exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Do not take more than your recommended dose. High doses of furosemide may cause irreversible hearing loss.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Lasix will make you urinate more often and you may get dehydrated easily. Follow your doctor's instructions about using potassium supplements or getting enough salt and potassium in your diet.

While using Lasix, you may need frequent blood tests.

Keep using this medicine as directed, even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medicine for the rest of your life.

If you need surgery, tell the surgeon ahead of time that you are using Lasix.

Store at room temperature away from moisture, heat, and light. Throw away any Lasix oral solution (liquid) 90 days after opening the bottle, even if it still contains unused medicine.

See also: Dosage Information (in more detail)

What happens if I miss a dose?

Lasix is sometimes used only once, so you may not be on a dosing schedule. If you are using the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include feeling very thirsty or hot, heavy sweating, hot and dry skin, extreme weakness, or fainting.

What should I avoid while taking Lasix?

If you also take sucralfate, take it at least 2 hours before or after you take furosemide.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Avoid becoming dehydrated. Follow your doctor's instructions about the type and amount of liquids you should drink while you are taking Lasix.

Drinking alcohol with this medicine can cause side effects.

What are the possible side effects of Lasix

Get emergency medical help if you have signs of an allergic reaction to Lasix: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • ringing in your ears, hearing loss;

  • confusion, drowsiness, problems with memory or speech;

  • jaundice (dark urine, yellowing of the skin or eyes);

  • severe pain in your upper stomach spreading to your back;

  • nausea, vomiting, loss of appetite, sweet or musty breath odor;

  • pale skin, easy bruising or bleeding;

  • sudden weakness or ill feeling, fever, chills, sore throat;

  • signs of an electrolyte imbalance - dry mouth, increased thirst, mood changes, muscle pain or weakness, lack of energy, fast heartbeats, little or no urination;

  • kidney problems - little or no urination, painful or difficult urination, swelling in your feet or ankles, feeling tired or short of breath; or

  • severe skin reaction - 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 the face or upper body) and causes blistering and peeling.

Common Lasix side effects may include:

  • numbness or tingling;

  • headache, dizziness; or

  • blurred vision.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Lasix?

Taking this medicine with alcohol or with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking Lasix with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Furosemide can harm your kidneys. This effect is increased when you also use certain other medicines, including: antivirals, chemotherapy, injected antibiotics, medicine for bowel disorders, medicine to prevent organ transplant rejection, injectable osteoporosis medication, and some pain or arthritis medicines (including aspirin, Tylenol, Advil, and Aleve).

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • chloral hydrate;

  • digoxin, digitalis;

  • lithium;

  • phenytoin; or

  • heart or blood pressure medicine.

This list is not complete. Other drugs may interact with furosemide, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about Lasix.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Lasix only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service 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. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. 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 1996-2016 Cerner Multum, Inc. Version: 14.01. Revision Date: 2016-05-12, 8:54:39 AM.

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