Furosemide, commonly known as the pharmaceutical brand Lasix, is a strong diuretic medication used to decrease fluid and salt retention resulting from various health disorders. It reduces swelling, or edema, which can be uncomfortable and lead to further health problems. Weight loss can occur when taking furosemide due to fluid loss; sometimes this is a serious side effect.
People with kidney disease such as nephritic syndrome, liver disease such as cirrhosis, and congestive heart failure or congenital heart defects are prone to fluid retention. Furosemide is effective at relieving this problem, and it is also used for treating high blood pressure, according to the National Institutes of Health's PubMed Health website.
How It Works
Furosemide is classified as a loop diuretic that causes the kidneys to eliminate excessive salt and water from the body through urination, explains Drug Watch. This prevents or decreases fluid accumulation in the ankles, legs and even in the lungs. Although loop diuretics are potent medications, some patients may need to take another diuretic in addition to furosemide. Some weight loss can occur when fluid is eliminated, but rapid and excessive weight loss is a sign of a serious condition.
Rapid and excessive weight loss when taking furosemide calls for immediate medical attention. The product labeling carries a warning because potent diuretics can cause severe dehydration and electrolyte depletion. Other signs of this problem besides weight loss include thirst, muscle cramps, weakness, headache, dizziness, blurred vision, confusion, upset stomach, nausea and vomiting.
Some other uncommon but serious side effects associated with furosemide also call for immediate medical attention, notes by PubMed Health. These include fever, sore throat, ringing in the ears, hearing loss, abnormal bruising or bleeding, trouble swallowing, breathing problems or a rash with peeling skin. Furosemide can cause extra sensitivity to ultraviolet light, or photosensitivity, which increases the risk of severe sunburn. PubMed Health advises wearing sunscreen, protective clothing and sunglasses when you are outside during the day and avoiding prolonged exposure to sunlight.
Furosemide is available in tablet and liquid forms. Patients usually take it either twice per day or once per day in the morning. If you take furosemide and you miss a dose, do not take two doses to make up for it, as this can cause or worsen side effects.