Letairis

Generic Name: ambrisentan (am bri SEN tan)
Brand Names: Letairis

What is Letairis?

Letairis (ambrisentan) prevents thickening of the blood vessels, especially those in the lungs and heart. Letairis also lowers blood pressure in your lungs, helping your heart pump blood more efficiently.

Letairis is used to treat pulmonary arterial hypertension (PAH). It improves your ability to exercise and prevents your condition from getting worse.

Letairis may also be used for purposes other than those listed in this medication guide.

Important information about Letairis

Letairis can harm an unborn baby or cause birth defects. Do not use if you are pregnant. If you are a woman of child-bearing potential, you will need to have a negative pregnancy test before you start treatment with Letairis. You will also be re-tested each month during your treatment. You will be required to use two forms of birth control to prevent pregnancy during your treatment, and for at least 1 month after your treatment ends. If you have had a tubal ligation or are using a copper IUD, you will not need to use a second form of birth control. Do not stop taking Letairis without first talking to your doctor. You may need to use less and less before you stop the medication completely.

Letairis is available only under a special program called LEAP (Letairis Education and Access Program). You must be registered in the program and sign agreements to use birth control and undergo pregnancy and blood testing as required by the program. Read all program brochures and agreements carefully.

Before taking Letairis

Your should not use Letairis if you are allergic to ambrisentan, if you have moderate or severe liver disease, or if you are pregnant.

To make sure you can safely take Letairis, tell your doctor if you have any of these other conditions:

• anemia (low red blood cell counts);

• a history of liver problems; or

• if you are pregnant or plan to become pregnant while taking Letairis.

If you are a woman of child-bearing potential, you will need to have a negative pregnancy test before you start treatment with Letairis. You will also be re-tested each month during your treatment.

FDA pregnancy category X.

See also: Letairis pregnancy and breastfeeding warnings (in more detail)

Letairis can harm an unborn baby or cause birth defects. Do not use Letairis if you are pregnant. Tell your doctor right away if you become pregnant during treatment. You will be required to use two forms of birth control to prevent pregnancy during your treatment, and for at least 1 month after your treatment ends. If you have had a tubal ligation or are using a copper IUD (intrauterine device), you will not need to use a second form of birth control. Recommended combinations of birth control forms include:

• 1 hormone form (birth control pill, skin patch, implant, vaginal ring, or injection) plus 1 barrier form (condom, diaphragm with spermicide, or cervical cap with spermicide).

• a condom and a female barrier form together (diaphragm with spermicide, or cervical cap with spermicide).

• a partner's vasectomy plus 1 hormone form or 1 barrier form.

Talk with your doctor about the use of emergency contraception if you have unprotected sex or if you believe your form of contraception has failed. It is not known whether ambrisentan passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using Letairis. Ambrisentan may lower a man's sperm count and could affect fertility (your ability to have children).

How should I take Letairis?

Take Letairis exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Letairis is available only under a special program called LEAP (Letairis Education and Access Program). You must be registered in the program and sign agreements to use birth control and undergo pregnancy and blood testing as required by the program. Read all program brochures and agreements carefully.

Before you start treatment with Letairis, your doctor may perform blood tests to make sure it is safe for you to take this medication. Your blood will need to be tested often during treatment. Visit your doctor regularly.

Letairis can be taken with or without food.

Do not crush, chew, or split the tablet. Swallow the pill whole.

Do not stop taking Letairis without first talking to your doctor. You may need to use less and less before you stop the medication completely.

Store this medicine at room temperature away from moisture and heat. Keep this medicine in its original container.

See also: Letairis dosage (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include feeling like you might pass out.

What should I avoid while using Letairis?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Letairis side effects

Get emergency medical help if you have any of these signs of an allergic reaction to Letairis: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have a serious side effect such as:

• anxiety, sweating, pale skin, severe shortness of breath, wheezing, gasping for breath, cough with foamy mucus, chest pain, fast or uneven heart rate;

• swelling of the feet, ankles, or legs;

• pounding heartbeats or fluttering in your chest; or

• nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious Letairis side effects may include:

• headache;

• stomach pain, vomiting, constipation;

• stuffy nose, sinus pain, sore throat; or

• warmth, redness, or tingly feeling under your skin.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Letairis side effects (in more detail)

What other drugs will affect Letairis?

Before you take Letairis, tell your doctor if you are using cyclosporine (Sandimmune, Neoral, Gengraf).

This list is not complete and other drugs may interact with Letairis. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?

• Your doctor or pharmacist can provide more information about Letairis.