Lasix, also known as furosemide, is adiureticand is a prescription medication commonly used after surgery.
Triggering the body to increase urine output can help treat these conditions.
Why It’s Used After Surgery
Lasix is used after surgery for a variety of reasons.

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Removing this extra fluid can improve heart and lung function.
Swelling, especially in the legs, can also be an issue after surgery.
For these patients, removing this extra fluid in the first days of recovery is helpful.
The same is true after experiencing kidney failure, or even after a kidney transplant.
Some patients take Lasix routinely at home for a variety of kidney, liver, and heart conditions.
However, it is rarely given as an injection into the muscle.
In the hospital setting, it is typically given as a pill or an IV injection.
It is a prescription medication.
Lasix changes the electrolyte balance in the bodyparticularly salt and potassium.
This can lead to cramping, diarrhea, nausea, and vomiting.
Risks
People who are pregnant should take Lasix only if the benefits outweigh the potential risks.
Pregnant women who take Lasix are known to have higher birth weight babies than they would otherwise.
This medication can also decrease breast milk production and can be passed to an infant through milk.
This is typically only a problem when the medication is given in very large doses through an IV.
When taking Lasix, the loss of potassium is a known risk.
This medication should not be taken by individuals with pancreatitis, an often painful inflammation of the pancreas.
This medication can worsen gout or trigger a flare of gout.
2018;13(4):e0196088.
doi:10.1371/journal.pone.0196088
Khan TM, Patel R, Siddiqui AH.Furosemide.
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2019 Jan-.
Updated April 5, 2021.