Losartan is used to treat high blood pressure (hypertension) and to help protect the kidneys from damage due to diabetes. It is also used to lower the risk of strokes in patients with high blood pressure and an enlarged heart. Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems. Losartan belongs to a class of drugs called angiotensin receptor blockers (ARBs). It works by relaxing blood vessels so that blood can flow more easily.
Dizziness or lightheadedness 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.
Tell your doctor right away if any of these unlikely but serious side effects occur: fainting, symptoms of a high potassium blood level (such as muscle weakness, slow/irregular heartbeat).
Although losartan may be used to prevent kidney problems or treat people who have kidney problems, it may also rarely cause serious kidney problems or make them worse. Your doctor will check your kidney function while you are taking losartan. Tell your doctor right away if you have any signs of kidney problems such as a change in the amount of urine.
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.
Before taking losartan, 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: liver disease, severe loss of body water and minerals (dehydration).
This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
This medication may increase your potassium levels. Before using potassium supplements or salt substitutes that contain potassium, consult your doctor or pharmacist.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
This medication is not recommended for use during pregnancy due to the risk for harm to an unborn baby. Consult your doctor for more details. (See also Warning section.)
It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.