Losartan

GENERIC NAME: losartan

DRUG CLASS AND MECHANISM
Losartan is an oral medication that belongs to a class of drugs called angiotensin receptor blockers (ARBs). Other ARBs include irbesartan (Avapro), valsartan (Diovan), and candesartan (Atacand). Angiotensin, formed in the blood by the action of angiotensin converting enzyme (ACE), is a powerful chemical that attaches to angiotensin receptors found in many tissues but primarily on smooth muscle cells of blood vessels. Angiotensin's attachment to the receptors causes the blood vessels to narrow (vasoconstrict) which leads to an increase in blood pressure (hypertension). Losartan (more specifically, the chemical formed when the liver converts the inactive losartan into an active chemical) blocks the angiotensin receptor. By blocking the action of angiotensin, losartan dilates blood vessels and thereby reduces blood pressure. Losartan was approved by the FDA in April 1995.

PRESCRIPTION: Yes

GENERIC AVAILABLE: Yes

PREPARATIONS: Tablets: 25, 50 and 100 mg

PRESCRIBED FOR
Losartan is used for treating hypertension, left ventricular hypertrophy (increase in muscle) and diabetic nephropathy (kidney disease). It may be used alone or in combination with other drugs.

DOSING
The usual starting dose of losartan for adults is 50 mg daily. The maximum dose is 100 mg daily. The total daily dose may be divided and administered twice daily. Losartan may be given with or without food.

The starting dose of losartan for pediatric patients 6 years of age or older is 0.7 mg/kg up to 50 mg once daily. Doses more than 1.4 mg/kg or 100 mg daily have not been evaluated in pediatric patients.

DRUG INTERACTIONS
Inhibitors of cytochrome P450 enzymes such as fluconazole (Diflucan) reduced the formation of the active drug metabolite in laboratory studies. Therefore, caution should be used when adding losartan in a patient taking Nizoral, as reduced activity of losartan may occur.

Losartan may increase levels of blood potassium which can lead to serious heart problems (arrhythmias). Therefore, concomitant use of other substances that increase blood-such as potassium-sparing diuretics (for example, spironolactone (Aldactone), triamterene, and amiloride), potassium supplements, or salt substitutes containing potassium--may lead to dangerous increases in serum potassium.

The antihypertensive effect of losartan may be reduced by nonsteroidal antiinflammatory drugs (for example, indomethacin, ibuprofen, aspirin , and naproxen).

USES
This drug 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. This drug works by blocking the hormone angiotensin thereby relaxing blood vessels, causing them to widen. High blood pressure reduction helps prevent strokes, heart attacks, and kidney problems.

OTHER USES
This drug may also be used to treat congestive heart failure.

HOW TO USE
Take this medication by mouth, usually once daily or as directed by your doctor. You may take this drug with or without food. Use this medication regularly in order to get the most benefit from it. To help you remember, use it at the same time each day. Do not take potassium supplements or salt substitutes containing potassium without talking to your doctor or pharmacist first. This medicine can raise your potassium levels, which rarely can cause serious side effects such as muscle weakness or very slow heartbeats. Tell your doctor immediately if these effects occur. The dosage is based on your medical condition and response to therapy. For the treatment of high blood pressure, it may take 3 to 6 weeks before the full benefit of this drug occurs. It is important to continue taking this medication even if you feel well. Most people with high blood pressure do not feel sick.

SIDE EFFECTS
You may experience dizziness, lightheadedness, blurred vision, or a stuffy nose as your body adjusts to the medication. If any of these effects persist or worsen, notify your doctor or pharmacist promptly. Tell your doctor immediately if any of these unlikely but serious side effects occur: fainting, decreased sexual ability. Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: change in the amount of urine, stomach/abdominal pain, severe nausea, yellowing eyes or skin, dark urine, unusual fatigue, muscle pain. An allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include: rash, itching, swelling (especially of the face, lips, tongue, or throat), severe dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.

PRECAUTIONS
Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, liver disease, high blood levels of potassium, heart problems, severe dehydration (and loss of electrolytes such as sodium), diabetes (poorly controlled), any allergies (especially to ACE inhibitors such as captopril, lisinopril). This drug may make you dizzy; use caution engaging in activities requiring alertness such as driving or using machinery. Limit alcoholic beverages. To minimize dizziness and lightheadedness, get up slowly when rising from a seated or lying position. Before having surgery, tell your doctor or dentist that you are taking this medication. Caution is advised when using this drug in the elderly because they may be more sensitive to the effects of the drug, especially the dizziness effect. This medication should be used only when clearly needed during the first three months of pregnancy. It is not recommended for use during the last six months of the pregnancy due to the risk for fetal harm. Discuss the risks and benefits with your doctor. See also the Warning section. It is not known if this drug passes into breast milk. Breast-feeding is not recommended due to the potential harm to the nursing infant. Consult your doctor before breast-feeding.

OVERDOSE
If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US national poison hotline at 1-800-222-1222. Canadian residents should call their local poison control center directly. Symptoms of overdose may include unusually fast or slow heartbeat, severe dizziness or fainting.

MISSED DOSE
If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

STORAGE
Store at room temperature (77 degrees F or 25 degrees C) away from light and moisture. Brief storage between 59 and 86 degrees F (15 to 30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.

WARNING: This drug can cause serious fetal harm (possibly death) if used during the last six months of pregnancy. If you become pregnant or think you may be pregnant, contact your doctor immediately.

Note : This product information is intended only for residents of the India. Taj Pharmaceuticals Limited, medicines help to treat and prevent a range of conditions—from the most common to the most challenging—for people around the world.