SIDE EFFECTS: Dizziness, lightheadedness, headache, or blurred vision may occur as your body adjusts to the medication. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. This medication may cause a serious loss of body water (dehydration) and salt/minerals. Tell your doctor right away if you have any of these unlikely but serious side effects: muscle cramps, weakness, unusual tiredness, confusion, severe dizziness, fainting, drowsiness, unusual dry mouth/thirst, nausea, vomiting, fast/irregular heartbeat. Tell your doctor right away if any of these unlikely but serious side effects occur: signs of kidney problems (such as change in the amount of urine), numbness/tingling/pain/redness/swelling of the arms/legs, hearing changes (such as ringing in the ears, temporary or permanent decreased hearing/deafness), stomach/abdominal pain, yellowing eyes/skin. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking furosemide, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney problems, liver problems, inability to make urine, gout, lupus. If you have diabetes, furosemide may affect your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication, exercise program, or diet. Furosemide may reduce the potassium level in your blood. Your doctor may instruct you to add potassium-rich foods to your diet (such as bananas, orange juice) or prescribe potassium supplements to prevent potassium loss. Ask your doctor for more details. This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness. This drug may make you dizzy or blur your vision. Alcohol or marijuana can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana. Severe sweating, diarrhea, or vomiting can increase the risk of dehydration. Report prolonged diarrhea or vomiting to your doctor. Follow your doctor's instructions about the amount of fluids you can drink. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Babies born early (premature infants) and children may be more sensitive to certain effects of this drug, such as kidney stones. Older adults may be more sensitive to the effects of this drug, especially dizziness and water/mineral loss. During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. This drug passes into breast milk and may affect milk production. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: See also the How to Use section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: desmopressin, ethacrynic acid, lithium. Some products have ingredients that could raise your blood pressure or worsen your swelling. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen). This medication may interfere with certain lab tests (such as thyroid hormone levels), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: fainting, severe weakness, a severe decrease in the amount of urine.