Should you drink a lot of water when taking Lasix?

You should avoid becoming dehydrated while taking Lasix, but you do not need to drink a lot of extra water unless your healthcare provider recommends it. In some cases, you may need to restrict the amount of fluids you drink if you have kidney, liver, or heart problems.

For example, for some people with severe heart failure, doctors may recommend drinking less than 2 liters (about 66 ounces) of fluid per day, including water and all other fluids.

Ask your doctor the specific amount of water and other fluids you should drink everyday to avoid getting dehydrated, and follow those directions.

Your doctor may ask you to regularly weigh yourself to check for fluid swelling (edema) and weight gain.

Why is Lasix prescribed?

• Lasix (generic name: furosemide) is a loop diuretic (often called a water pill) that works in the kidney to help remove extra fluid and salt from the body. It is a strong diuretic that helps you to urinate more to eliminate extra fluid, and lower swelling and fluid retention (edema).
• It is often used in people with high blood pressure, congestive heart failure, liver disease (cirrhosis of the liver), and kidney disease.
• Lowering blood pressure may lower your risk of a stroke or heart attack.

You should not use this medicine if you cannot urinate (called anuria).

Related: Lasix: 7 things you should know

How much water should I drink in one day?

In general, many healthcare professionals recommend healthy people drink about eight, 8-ounce glasses of water throughout the day, but this is not a hard-and-fast guideline. This recommendation may NOT apply if you are taking Lasix, so you should ask your doctor for a specific amount. If you experience extreme thirst while taking Lasix, you should call your doctor right away.

Recommendations on total water intake per day can vary based on your health, location, physical activity, environment, diet, and if you are pregnant or breastfeeding.

The total amount of fluid (not just water) to consume everyday (which includes fluid from water, other liquids, and food) is outlined by the U.S. National Academies of Sciences, Engineering, and Medicine. They determined that an adequate intake in a healthy adults is about:

• 15.5 cups (3.7 liters) of total fluid per day for men
• 11.5 cups (2.7 liters) of total fluid per day for women

What are the warning signs of being dehydrated?

The most common signs of dehydration in an adult include:

• weakness
• extreme thirst
• less frequent urination
• dark-colored urine
• fatigue
• dizziness
• confusion
• low blood pressure
• fainting

Becoming dehydrated can cause you to feel dizzy or unsteady, and may lead to a serious fall. Avoid getting up too fast from a sitting or lying position, especially when you first start taking Lasix. This can be more extreme in the elderly.

In hot weather or during exercise you may sweat more and lose body fluid and electrolytes, so you may need to drink more water. Follow your healthcare providers instructions about:

• the amount and types of liquids to drink
• how much salt you should eat
• using potassium supplements or potassium substitutes
• if you can drink alcohol, and how much
• a regular exercise routine
• getting enough salt, potassium or other electrolytes in your diet.

Lasix can lead to a dangerous depletion of electrolytes (such as sodium or potassium). This may cause side effects like muscle cramps. muscle twitches, weakness or an irregular heartbeat. The risk is greater in people on a low-salt diet or taking certain medicines.

Be sure to follow your doctor’s instructions for any lab blood or urine testing and electrolyte supplements (like potassium) while taking this medicine.

If you take Lasix, tell your doctor right away if you have any of these side effects:

• extreme thirst or a dry mouth
• muscle pain or cramp
• a decrease in urine, no urination, or painful or difficult urination
• swelling in your feet or ankles
• A rapid weight gain or 2 to 3 lbs (1 kg) in one day or 5 lbs (2 kg) in one week
• weakness or lack of energy, feeling drowsy
• low blood pressure
• fast heart beats or an irregular heartbeat
• lightheadedness or dizziness
• fainting
• shortness of breath
• increased urination with extreme thirst, dry mouth, fruity breath odor (may signal high blood sugar)
• confusion
• weakness
• mood changes or feeling restless
• unusual bleeding or bruising
• nausea or vomiting
• dark urine, jaundice (yellowing of the skin or eyes)
• stomach pain
• loss of appetite
• ringing in the ears or a hearing loss

Do not take more than your recommended dose of Lasix. Overdose symptoms may include feeling very thirsty or hot, heavy sweating, hot and dry skin, extreme weakness, or fainting. If you’ve taken too much Lasix, call 911 for emergency medical help or call the Poison Help line at 1-800-222-1222.

These are not all of the side effects that may occur with Lasix (furosemide). If you have questions about side effects, call your doctor.

This is not all the information you need to know about Lasix (furosemide) for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.

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