Lasix

Generic Name: Furosemide

  • What is Lasix?

    Lasix is a diuretic (water pill) used to treat high blood pressure. It is also used to treat swelling due to fluid retention associated with heart failure or kidney or liver disease.

  • What is the most important information I should know about Lasix?

    Since blood pressure declines gradually, it may be several weeks before you get the full benefit of Lasix. You must continue taking it even if you are feeling well. Lasix does not cure high blood pressure; it only keeps it under control.

    Do not drive or perform other possibly unsafe tasks until you know how you react to Lasix; this drug may cause dizziness or blurred vision. These effects may be worse if you take it with alcohol or certain medicines.

    Lasix may cause dizziness, lightheadedness, or fainting; alcohol, hot weather, exercise, or fever may increase these effects. To prevent these side effects, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects.

    Promptly notify your doctor if you become very thirsty, have a dry mouth, become confused, or develop muscle cramps/weakness.

    Lasix may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.

    Check with your doctor before you use a salt substitute or other product that has potassium in it.

    Lasix may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to Lasix. Use sunscreen or wear protective clothing if you must be outside for more than a short time.

    Tell your doctor or dentist that you take Lasix before you receive any medical or dental care, emergency care, or surgery.

  • Who should not take Lasix?

    Do not use Lasix if you cannot urinate or if you are sensitive to the drug or any of its ingredients.

  • What should I tell my doctor before I take the first dose of Lasix?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Lasix. Also, talk to your doctor about your complete medical history, especially if you have abnormal electrolyte levels, an allergy to sulfa medicines, diabetes, fluid in your abdomen, gout (a complex form of arthritis), a history of heart attack, hearing problems, or kidney or liver disease. Also tell your doctor if you have low urine output, lupus (a disease that affects the immune system), porphyria (a blood disorder), or if you are dehydrated or on a low-salt diet. Also tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What is the usual dosage?

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

    Blood Pressure

    Adults: The usual starting dose is 80 milligrams (mg) divided into two smaller doses. Your doctor will adjust the doses and may add other high blood pressure medications if Lasix does not adequately reduce your blood pressure.

    Children: Your doctor will prescribe the appropriate dose for your child based on their body weight.

    Fluid Retention

    Adults: The usual starting dose is 20-80 mg. Your doctor will prescribe the appropriate dose for you and will increase your dose as needed, until the desired effect is achieved.

  • How should I take Lasix?

    Take Lasix exactly as prescribed by your doctor. To reduce nighttime urination, take Lasix early in the day unless otherwise directed by your doctor. Lasix is taken with or without food.

  • What should I avoid while taking Lasix?

    Avoid using cough and cold products while taking Lasix. They contain ingredients that may increase your blood pressure.

    Use alcohol with caution. Alcohol may increase the side effects of Lasix.

    Do not drive or perform other possibly unsafe tasks until you know how you react to Lasix; this drug may cause dizziness or blurred vision.

    Do not sit or stand up quickly when you begin treatment with Lasix, especially in the morning. Sit or lie down at the first sign of dizziness or lightheadedness.

    Avoid the sun, sunlamps, or tanning booths until you know how you react to Lasix. Use sunscreen or wear protective clothing if you must be outside for more than a short time.

  • What are possible food and drug interactions associated with Lasix?

    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 doctor before combining Lasix with the following: antibiotics such as amikacin and gentamicin, blood pressure medications known as ACE inhibitors, aspirin and other salicylates, doxazosin, chloral hydrate, corticosteroids, digoxin, ethacrynic acid, ibuprofen, indomethacin, lithium, narcotics such as codeine, norepinephrine, succinylcholine, sucralfate, terazosin, and tubocurarine.

  • What are the possible side effects of Lasix?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: blood disorders, calf pain or tenderness, confusion, dizziness, dry mouth, fast or irregular heartbeat, lightheadedness, loss of appetite, muscle spasms, reddish or purplish spots on the skin, restlessness, ringing in the ears, sensitivity to sunlight, yellow eyes and skin

  • Can I receive Lasix if I am pregnant or breastfeeding?

    The effects of Lasix during pregnancy and breastfeeding are unknown. Tell your doctor immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of Lasix?

    Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and go back to your regular schedule. Do not take two doses at once.

  • How should I store Lasix?

    Store at room temperature in a tight, light-resistant container. Exposure to light may cause Lasix to develop a slight discoloration. Do not take discolored tablets.

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