Drug Name

Cozaar (Losartan)

Drug Uses

Losartan is indicated for the treatment of hypertension. It may be used alone or in combination with other agents. It has less of an effect in black patients, similar to ACE inhibitors, such as captopril (Capoten), enalapril (Vasotec), and lisinopril (Zestril).

How Taken

Losartan may be given with or without food. Losartan is metabolized in the liver by cytochrome P450 enzymes to an active metabolite that is responsible for most of the drug activity. Reduction in dose by 50% is suggested in patients with impaired liver function.

Drug Class and Mechanism

Losartan and its primary metabolite block the angiotensin receptor found in many tissues, primarily in vascular smooth muscle. Angiotensin, formed by the action of angiotensin converting enzyme (ACE), is a powerful chemical that causes blood vessel narrowing (vasoconstriction) which can lead to elevated blood pressure (hypertension).

Missed Dose

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication.

Storage

Tablets should be stored at room temperature in a tightly closed, light resistant container.

Warnings/Precautions

Use caution when driving, operating machinery, or performing other hazardous activities. Losartan may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Also use caution when rising from a sitting or lying position. Use alcohol cautiously. Alcohol may further lower blood pressure and increase drowsiness and dizziness while taking losartan. Do not use salt substitutes or take potassium supplements without first talking to your doctor. Losartan can affect potassium levels in the body. When used in the second or third trimester of pregnancy, drugs that act by the same mechanism as losartan can cause injury and even death to the fetus. Losartan should not be used during pregnancy. When pregnancy is detected, losartan should be stopped as soon as possible. Losartan is present in rat milk, and is toxic to rat neonates. Therefore, it should be avoided in nursing mothers

Possible Side Effects

In studies of over 4000 patients, including 1200 treated for over 6 months and 800 for over 1 year, the overall incidence of side effects was similar to placebo. Losartan is generally well tolerated. Side effects reported included diarrhea, muscle cramps, dizziness, insomnia, and nasal congestion.

More Information

Stop taking losartan and contact your doctor immediately or seek emergency medical treatment If you experience any of the following serious side effects: an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives); or little or no urine. Other side effects are less serious. Continue to take losartan and talk to your doctor if you experience diarrhea or upset stomach, muscle pain or cramps, dizziness, or insomnia. Side effects, other than those listed here, may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.