What is Furosemide?

How it works:
Furosemide is a potent diuretic which works by blocking the absorption of salt and fluid in the kidney tubules causing an increase in urine output.

Cautions:
Keep plenty of water available for your pet to drink. Furosemide can make your pet’s skin more sensitive to sunlight. There are possible adverse interactions with other drugs, so fully disclose to your veterinarian what you are giving your pet. This medication should not be used in pregnant or nursing animals.

What is the most important information I should know about furosemide: Do not give this medication if your pet is not urinating. Tell your veterinarian if your pet has kidney or liver disease, diabetes, or an allergy to sulfa drugs. Furosemide can make the pet¿s skin more sensitive to sunlight and sunburn may occur. Periodic blood tests as well as kidney or liver function tests may be necessary. Furosemide will make the pet urinate more often and the pet should have drinking water readily available to prevent dehydration and electrolyte imbalance.

What is furosemide: Furosemide is a loop diuretic (water pill) used to treat fluid retention (edema) in dogs and cats with congestive heart failure, liver disease, or certain kidney disease. Furosemide is also used to treat high blood pressure. Furosemide is available by prescription in 12.5mg (round yellow), 20mg (round white), 40mg (round white), 50mg (round yellow), and 80mg (round white) tablets and 60 ml Furosemide Oral Solution containing 10mg/ml. The usual dose of furosemide in dogs and cats is 1-2mg/pound once or twice a day (at 6 to 8 hour intervals). Cats will usually get the lower dose. Higher doses can be given depending on the severity of symptoms. Discard the opened bottle of Oral Solution after 90 days. Furosemide may also be used for purposes other than those listed in this guide.

What should I discuss with my veterinarian before giving furosemide to my pet: Do not give this medication if your pet is not urinating. Tell your veterinarian if your pet has kidney or liver disease, diabetes, or an allergy to sulfa drugs. Tell your veterinarian if your pet is pregnant or lactating.

How should this medication be given: Give this medication exactly as directed by your veterinarian. Do not give larger amounts, or give it for longer than recommended by your veterinarian. Your veterinarian may occasionally change the dose to make sure your pet gets the best results from this medication. Furosemide will make the pet urinate more often and the pet should have drinking water readily available to prevent dehydration and electrolyte imbalance. Periodic blood tests as well as kidney or liver function tests may be necessary. Store this medication at room temperature away from heat, light, and moisture.

What happens if I miss giving a dose: Furosemide is sometimes used only once, so that there may not be a dosing schedule. If you are giving furosemide regularly, give the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and wait until the next regularly scheduled dose. Do not give a double dose of the medication.

What happens if I overdose the pet: Seek emergency veterinary medical attention if you believe you have given your pet too much medication. Symptoms of furosemide overdose may include loss of appetite, weakness, dizziness, confusion, fainting.

What should I avoid while giving furosemide: Avoid allowing the pet to become dehydrated. Keep plenty of water available for the pet to drink. Furosemide can make the pet¿s skin more sensitive to sunlight and sunburn may occur.

What are the possible side effects of furosemide: If any of the following serious side effects occur, stop giving furosemide and seek emergency veterinary medical attention; an allergic reaction (hives, difficulty breathing, swelling of the face, lips, tongue, or throat). Stop giving furosemide and call your veterinarian at once if any of these serious side effects occur; dry mouth, thirst, nausea, and vomiting; weakness, drowsiness, restlessness; irregular heartbeat; muscle pain or weakness; urinating less than usual or not at all; bleeding, unusual weakness; hair loss; "bulls-eye" lesions; vesicles around mouth, ears, and groin; hearing loss; nausea, stomach pain; fever; loss of appetite; dark urine; jaundice. Continue giving furosemide and talk with your veterinarian if any of these less serious side effects should occur; diarrhea, constipation, or stomach pain; headache; dizziness, or blurred vision. Side effects other than those listed in this guide may also occur. Talk to your veterinarian about any side effect that seems unusual or especially bothersome to your pet.

What other drugs will affect furosemide: If you give your pet sucralfate (Carafate), give it at least 2 hours before or after giving furosemide. Tell your veterinarian if your pet is being given digoxin (Lanoxin), steroids (such as prednisone), other blood pressure medications, Amikacin, gentamicin, tobramycin, salicylates such as aspirin (Vetrin), or indomethacin. Drugs other than those listed may also interact with furosemide. Tell your veterinarian about all the prescription and over the counter medications you are giving your pet. This includes vitamins, minerals, and herbal products.

Where can I get more information: Your pharmacist has additional information about furosemide written for health professionals that you can read.