Generic Name: furosemide (fure-OH-se-mide) (Injection route)
Medically reviewed by Drugs.com. Last updated on April 20, 2021.
Commonly used brand name(s)
In the U.S.
- Furomide M.D.
Available Dosage Forms:
Therapeutic Class: Cardiovascular Agent
Pharmacologic Class: Diuretic, Loop
Uses for Lasix
Furosemide injection is used to help treat fluid retention (edema) and swelling that is caused by congestive heart failure, liver disease (cirrhosis), kidney disease, or other medical conditions.
Furosemide belongs to a group of medicines called loop diuretics or "water pills". It works by acting on the kidneys to increase the flow of urine.
This medicine is to be given only by or under the direct supervision of a doctor.
Before using Lasix
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of furosemide injection in children. However, premature babies are more likely to have unwanted effects (e.g., kidney stones, hearing problems), which may require caution in patients receiving furosemide injection.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of furosemide injection in the elderly. However, elderly patients are more likely to have age-related liver, kidney, or heart problems, which may require caution and an adjustment in the dose for patients receiving furosemide injection.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Amikacin Liposome
- Amtolmetin Guacil
- Arsenic Trioxide
- Chloral Hydrate
- Choline Salicylate
- Ethacrynic Acid
- Flufenamic Acid
- Mefenamic Acid
- Niflumic Acid
- Nimesulide Beta Cyclodextrin
- Salicylic Acid
- Sodium Salicylate
- Tiaprofenic Acid
- Tolfenamic Acid
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Allergy to sulfa drugs (such as sulfamethoxazole, sulfasalazine, sulfisoxazole, Azulfidine®, Bactrim®, Gantrisin®, or Septra®) or
- Bladder problem with urinating or
- Blood or bone marrow problems or
- Dehydration or
- Electrolyte imbalance (e.g., low sodium, calcium, magnesium, or potassium in the blood) or
- Enlarged prostate or
- Gout or
- Hearing problems or
- Hyperuricemia (high uric acid in the blood) or
- Hypovolemia (low blood volume) or
- Liver disease, severe (e.g., cirrhosis, hepatic coma) or
- Systemic lupus erythematosus (SLE) or
- Tinnitus (ringing in the ears) or
- Trouble urinating—Use with caution. May make these conditions worse.
- Anuria (not able to pass urine)—Should not be used in patients with this condition.
- Diabetes—This medicine may increase the amount of sugar in the blood.
- Hypertension (high blood pressure)—Your dose of antihypertensive medicines may need to be adjusted to prevent your blood pressure from falling too low.
- Hypoproteinemia (low protein in the blood) from a kidney problem or
- Radiocontrast nephropathy (kidney problem), history of—May cause side effects to become worse.
- Kidney disease, severe—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
Proper use of Lasix
This section provides information on the proper use of a number of products that contain furosemide. It may not be specific to Lasix. Please read with care.
A nurse or other trained health professional will give you or your child this medicine in a hospital. This medicine is given as a shot into a muscle or a vein.
Your doctor will give you a few doses of this medicine until your condition improves, and then switch you or your child to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.
Precautions while using Lasix
It is very important that your doctor check you or your child closely while you are receiving this medicine. This is to make sure this medicine is working properly. Blood or urine tests may be needed to check for unwanted effects.
Using this medicine while you are pregnant may cause your unborn baby to be bigger than normal. If you think you have become pregnant while using this medicine, tell your doctor right away.
This medicine may cause you or your child to lose more potassium from your body than normal (hypokalemia). This is more likely to occur if you have liver disease (e.g., cirrhosis), or if you are using this medicine together with steroids (cortisone-like medicines), adrenocorticotropic hormone (ACTH), large amounts of licorice, or laxatives for a long time. Tell your doctor if you become sick with severe or continuing nausea, vomiting, or diarrhea, and drink fluids to prevent getting dehydrated. Check with your doctor right away if you have one or more of these symptoms: dry mouth; increased thirst; muscle cramps; or nausea or vomiting.
Stop using this medicine and check with your doctor right away if you or your child have a sudden decrease in hearing or loss of hearing. You may also have dizziness or ringing in the ears with the hearing problem. Tell your doctor if you have dizziness or lightheadedness; a feeling of constant movement of self or surroundings; or a sensation of spinning.
Dizziness, lightheadedness, or fainting may occur, especially when you get up suddenly from a lying or sitting position. Getting up slowly may help. If the problem continues or gets worse, check with your doctor.
This medicine may cause an increase in blood sugar levels. If you or your child are diabetic and notice a change in the results of your blood or urine sugar tests, check with your doctor.
This medicine may make your skin more sensitive to sunlight. Use a sunscreen, hat, and protective clothing when you are outdoors. Avoid sunlamps and tanning beds.
Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.
Do not take other medicines unless they have been discussed with your doctor. This especially includes prescription or nonprescription (over-the-counter) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems.
Lasix side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur:
- Chest pain
- cough or hoarseness
- general feeling of tiredness or weakness
- lower back or side pain
- painful or difficult urination
- shortness of breath
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- swollen or painful glands
- tightness in the chest
- unusual bleeding or bruising
- unusual tiredness or weakness
Incidence not known
- Back or leg pains
- black, tarry stools
- bladder spasm
- bleeding gums
- blistering, peeling, or loosening of the skin
- bloody or cloudy urine
- blurred vision
- burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
- clay-colored stools
- cold sweats
- continuing ringing or buzzing or other unexplained noise in the ears
- coughing up blood
- dizziness, faintness, or lightheadedness when getting up from a lying or sitting position
- dry mouth
- fast heartbeat
- fever with or without chills
- flushed, dry skin
- fruit-like breath odor
- hearing loss
- increased hunger or thirst
- increased or decreased urination
- joint stiffness or swelling
- loss of appetite
- nausea or vomiting
- pain where a shot was given
- pains in the stomach, side, or abdomen, possibly radiating to the back
- pale skin
- pinpoint red spots on the skin
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- red, irritated eyes
- scaly skin
- skin rash
- swelling of the feet or lower legs
- troubled breathing with exertion
- unpleasant breath odor
- unusual weight loss
- yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
- Feeling of constant movement of self or surroundings
- hives or welts
- increased sensitivity of the skin to sunlight
- muscle spasm
- redness or other discoloration of the skin
- sensation of spinning
- severe sunburn
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Frequently asked questions
- Are losartan and losartan potassium the same drug or two different ones?
- How long after taking Lasix would you expect to urinate?
- Can you take Lasix for weight loss?
More about Lasix (furosemide)
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Patient Tips
- Drug Images
- Drug Interactions
- Compare Alternatives
- Support Group
- Pricing & Coupons
- En Español
- 49 Reviews
- Generic Availability
- Drug class: loop diuretics
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.