Lasix 40mg tablet contains an active ingredient called Furosemide which belongs to the medication class known as diuretics. It is used to treat edema (excessive water accumulation) and high blood pressure. Edema can be caused by various underlying issues such as heart, lung, kidney, or liver problems. This helps the kidneys to remove excess water, which is not needed by the body. Lasix 40mg tablet should not be taken if you are allergic to Furosemide or other sulphonamide-related medicines or any of the ingredients in the medication. Also, do not consume if you have anuria, impaired kidney function or kidney failure, severe kidney damage, very low levels of potassium, sodium, or other electrolytes, dehydration, low blood pressure, take potassium supplements or potassium-sparing diuretics, have liver cirrhosis or liver encephalopathy, suffer from Addison's disease, have digitalis poisoning, or if you are breastfeeding. Before starting the treatment with Lasix 40mg tablet, notify your doctor if you have hypovolaemia (low blood volume) or risk of low blood pressure, hypoproteinaemia (low levels of blood protein) due to kidney damage, liver congestion or other liver problems, kidney problems, diabetes or insulin use, advanced age or medications that lower blood pressure, prostate issues or difficulty in urinating, history of gout or abnormal blood condition, and upcoming blood or urine tests.