Ambrisentan lowers blood pressure in your lungs, helping your heart pump blood more efficiently.

Ambrisentan is used to treat pulmonary arterial hypertension (PAH) in adults. It improves your ability to exercise and prevents your condition from getting worse. Ambrisentan is sometimes used with a medicine called tadalafil (Adcirca).

For women, ambrisentan is available only from a certified pharmacy under a special program. You must be registered in the program and sign agreements to use birth control and undergo pregnancy and blood testing.

Ambrisentan may also be used for purposes not listed in this medication guide.

Do not use if you are pregnant or think you might be pregnant. You will need to take a pregnancy test before, during, and after treatment with ambrisentan. Use highly effective birth control while using ambrisentan and for at least 30 days after your last dose.

You should not use ambrisentan if you have idiopathic pulmonary fibrosis.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Take the medicine at the same time each day, with or without food.

Swallow the tablet whole and do not crush, chew, or break it.

You will need frequent medical tests.

Store ambrisentan in its original container at room temperature, away from moisture and heat.

Usual Adult Dose for Pulmonary Hypertension:

Initial dose: 5 mg orally once a day.

Comments:
-Consider increasing the dose to 10 mg orally once a day if 5 mg is tolerated.
-When used with tadalafil, the dose of either drug can be increased as needed and tolerated at 4-week intervals.

Uses:
-For the treatment of pulmonary arterial hypertension (WHO Group 1) to improve exercise ability and delay clinical worsening.
-For the treatment of pulmonary arterial hypertension (WHO Group 1) in combination with tadalafil to reduce the risks of disease progression and hospitalization for worsening pulmonary arterial hypertension, and to improve exercise ability.

You should not use ambrisentan if you are allergic to it, or if you have idiopathic pulmonary fibrosis (IPF).

Do not use ambrisentan if you are pregnant or think you might be pregnant. This medicine can cause serious birth defects. Tell your doctor right away if you miss a menstrual period or think you may have become pregnant.

You will need to have a negative pregnancy test before starting this treatment. You will be re-tested every month during your treatment, and 1 month after your last dose.

Even if you are not planning a pregnancy, you are considered able to become pregnant if:

• you have entered puberty (even if you have not yet started having periods);

• you have never had a hysterectomy or had your ovaries removed; or

• you have not gone through menopause (you have never gone 12 months in a row without a menstrual period).

While taking ambrisentan and for at least 30 days after your last dose, you must use a highly effective form of birth control or two methods together.

Recommended forms of birth control forms include:

• a tubal ligation, or a copper IUD (intrauterine device) or progesterone implant;

• one 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); or

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

Ambrisentan comes with patient instructions about acceptable forms of birth control to use while taking this medicine. Follow these directions carefully. Ask your doctor about emergency contraception if you have unprotected sex or if you believe your contraception has failed.

Tell your doctor if you have ever had:

• liver disease; or

• anemia (low red blood cell counts).

You should not breastfeed while you are using ambrisentan.

Ambrisentan may lower a man's sperm count and could affect fertility (your ability to have children).

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

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

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unless your doctor tells you otherwise, continue your normal diet.

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

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Ambrisentan may cause serious side effects. Call your doctor at once if you have:

• severe shortness of breath, wheezing, cough with foamy mucus, chest pain;

• swelling, tiredness, rapid weight gain;

• low red blood cells (anemia)--pale skin, unusual tiredness, feeling light-headed or short of breath, cold hands and feet; or

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

Common side effects of ambrisentan may include:

• swelling in your hands, legs, ankles, or feet;

• stuffy nose, sinus pain; or

• hot flashes, redness in your face.

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.

Tell your doctor about all your other medicines, especially:

• cyclosporine.

This list is not complete. Other drugs may affect ambrisentan, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Do not let anyone else take your medication.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.