This medication must not be used during pregnancy because it can harm an unborn baby. See also Precautions section.
In the US, ambrisentan is only available to female patients enrolled in the Letairis Risk Evaluation and Mitigation Strategy (REMS) program. Male patients do not need to be enrolled in this program to receive this medication. Only doctors and pharmacies enrolled in this program may prescribe or provide ambrisentan. Consult your doctor or pharmacist for more details about this program and about the risks and benefits of using this medication.
These requirements apply in the US. If you live in Canada or any other country, consult your doctor and pharmacist for your country's regulations.
Ambrisentan is used to treat high blood pressure in the lungs (pulmonary arterial hypertension). This condition is thought to be caused by increased levels of a certain natural substance (endothelin-1). This medication blocks the effects of endothelin-1, thereby helping to decrease the blood pressure in the lungs, slow the worsening of symptoms, and improve your ability to exercise.
This drug is controlled through a special program. A program worker will call you each month to make sure that you have gotten a pregnancy test if you are a woman who may become pregnant. See also Warning and Precautions sections.
Read the Medication Guide provided by your pharmacist before you start using ambrisentan and each time you get a refill. If you have any questions, consult your doctor or pharmacist.
Take this medication by mouth with or without food, usually once daily or as directed by your doctor. Do not crush, chew, or break the tablets.
The dosage is based on your medical condition, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Use this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day.
Do not stop taking this medication without consulting your doctor. Some conditions may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased.
Women who are pregnant or who may become pregnant should not handle the tablets or breathe the dust from this medication.
Tell your doctor if your condition persists or worsens.
Stuffy nose, runny nose, or flushing may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
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 you have any serious side effects, including: fast heartbeat, extreme tiredness, swelling ankles/feet, sudden/unexplained weight gain.
Other medications that are like ambrisentan may rarely cause very serious liver problems. Tell your doctor right away if you develop symptoms of liver disease, including: persistent nausea/vomiting, loss of appetite, severe stomach/abdominal pain, dark urine, yellowing eyes/skin.
This medication can decrease sperm production in some men, an effect that may lower male fertility. Consult your doctor for more details.
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.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking ambrisentan, tell your doctor or pharmacist if you are allergic to it; or to other endothelin receptor blockers (e.g., bosentan); 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, certain lung conditions (pulmonary fibrosis), anemia.
Older adults may be at greater risk for swelling ankles/feet while using this drug.
This medication must not be used during pregnancy. It may harm an unborn baby. If you are planning pregnancy, become pregnant, or think you may be pregnant, tell your doctor right away. Women who may become pregnant must have a negative pregnancy test before starting this medication, once a month while taking it, and for 1 month after stopping the medication. Consult your doctor for more details and to discuss reliable forms of birth control. Unless otherwise directed by your doctor, it is recommended that at least 2 reliable forms of birth control (e.g., birth control pills, condoms) be used while taking this medication and for 1 month after stopping the medication. Birth control should still be used, even if your partner had a vasectomy.
It is not known whether this medication passes into breast milk. Because of the possible risk to the infant, breast-feeding while using this medication is not recommended. Consult your doctor before breast-feeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
If overdose is suspected, contact a poison control center or emergency room right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe dizziness.
Do not share this medication with others.
Laboratory and/or medical tests (such as liver function test, monthly pregnancy test, hemoglobin level) will be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, take 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.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised October 2015. Copyright(c) 2015 First Databank, Inc.
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