What is Lasix? Uses, warnings & side effects

How to take Lasix

• Take your medicine as directed. Your dose may need to be changed several times to find what works best.

• The doctor may also instruct you to take dietary supplements such as potassium. Make sure to follow these directions. 

• Lasix tablets can be taken with a meal or on an empty stomach.

  • Take Lasix tablets with food if the dose upsets your stomach.

• Swallow the Lasix tablet whole with a glass of water.

• People who have trouble swallowing should talk to the pharmacist. It may be possible to crush the tablets and take them that way. 

• Store Lasix tablets in a closed container at room temperature and protect them from light.

What to do if you miss a dose of Lasix

• Take a missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the next dose as scheduled. 

• Do not take extra Lasix pills to make up for a missed dose.

Lasix contraindications - Who shouldn't take Lasix?

• This medicine is not right for everyone. 

• Never use Lasix if you:

  • Have had an allergic reaction to furosemide

  • Are not urinating

  • Have low electrolyte levels

• Healthcare providers do not use furosemide in people who are in a coma due to liver failure.

Lasix warnings

• Tell any doctor or other healthcare provider who treats you that you are using this medicine.

• Your doctor will regularly perform checkups and laboratory tests to monitor the effects of this medicine. Keep all appointments.

• Tell your doctor if you are pregnant or breastfeeding.

• Tell your doctor if you have:

  • Kidney disease

  • Liver disease (including cirrhosis)

  • Urinary retention

  • Enlarged prostate

  • Diabetes

  • Gout

  • Low blood pressure

  • Lupus

  • Allergies to sulfa drugs

  • Sodium restrictions on your diet

• Lasix can cause potentially serious problems, including: 

  • Dehydration

  • Electrolyte depletion, particularly low potassium or low sodium

  • Increased blood sugar levels

  • Changes in hearing

  • Low blood pressure

  • Drop in blood pressure when standing up, increasing the risk of falls and injuries

  • Swelling of the pancreas

This medicine may make your skin more sensitive to sunlight, increasing its vulnerability to sunburn. Try to stay out of direct sunlight. Wear sunscreen and protective clothing. Do not use sunlamps or tanning beds.

Lasix interactions & what to avoid when taking Lasix

• To avoid potentially hazardous drug interactions, tell the prescribing healthcare provider about all prescription drugs, over-the-counter medications, and supplements you use, particularly:

  • Other diuretics (the diuretic ethacrynic acid is not safe to take with Lasix)

  • NSAIDs such as aspirin, ibuprofen, or naproxen

  • Blood pressure medications, particularly ACE inhibitors or angiotensin II receptor blockers (ARBs)

  • Steroid medications 

  • Thyroid medications

  • Aminoglycoside antibiotics

  • The chemotherapy drug cisplatin

  • The heart failure drug digoxin

  • The immunosuppressants cyclosporine or methotrexate

  • The anticonvulsant drug phenytoin

  • The bipolar treatment lithium

  • Licorice supplements

• Tell other healthcare providers you are taking Lasix before they prescribe new medications.

• If you are taking sucralfate for your ulcers, don’t take a Lasix pill close to your sucralfate dose, or the Lasix dose may not work as well. Separate the doses by at least two hours. 

• Drugs that make you sleepy, like alcohol, narcotic pain medicine, or sleeping pills, are more likely to make you feel dizzy, lightheaded, or faint if you’re also taking a diuretic such as Lasix.

• People with high blood pressure should avoid medications that raise blood pressure, including over-the-counter stimulants, cold & flu medications, and weight loss aids.

Find more detailed information about furosemide interactions to avoid here.