Bosentan

Read the Medication Guide provided by your pharmacist before you start using bosentan and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually twice daily (in the morning and evening). If half tablets are needed for your dose, break the tablets along the score line. Do not break the tablets into quarters. Put the tablet(s) in a small amount of water to dissolve. Once dissolved, drink all the mixture right away. Unused half tablets may be stored back in the opened blister for up to 7 days.

The dosage is based on your medical condition, weight, 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 this drug is suddenly stopped. Your dose may need to be gradually decreased.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

Tell your doctor if your condition does not get better or if it gets worse.

Before taking bosentan, tell your doctor or pharmacist if you are allergic to it; 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, anemia.

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis). Alcohol may also increase the risk of serious liver problems.

This medication may contain aspartame. If you have phenylketonuria (PKU) or any other condition that requires you to limit/avoid aspartame (or phenylalanine) in your diet, ask your doctor or pharmacist about using this medication safely.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

This medication must not be used during pregnancy. It may harm an unborn baby. Discuss the use of reliable forms of birth control during treatment and for 1 month after the last dose. If you become pregnant or think you may be pregnant, tell your doctor right away. See also Warning section.

This medication passes into breast milk. Consult your doctor before breastfeeding.

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. Take your next dose at the regular time. Do not double the dose to catch up.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669. Symptoms of overdose may include: severe headache, severe dizziness, nausea, vomiting.

See also Warning section.

Dizziness, flushing, stuffy nose, or joint pain may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor 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/pounding heartbeat, unusual tiredness, swelling ankles/feet, unusual/sudden weight gain, fainting, shortness of breath, coughing up blood.

In men, this medication can decrease sperm production, which may affect the ability to father a child. Talk to 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: fever, swollen lymph nodes, 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/safety/medwatch-fda-safety-information-and-adverse-event-reporting-program.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Bosentan may rarely cause serious (possibly fatal) liver damage. Rarely, liver problems have happened in people after stopping treatment with bosentan. Your doctor will perform liver function tests before you start treatment and once a month during treatment. Tell your doctor right away if you notice nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, or dark urine.

This medication must not be used during pregnancy. It may harm an unborn baby. It is important to prevent pregnancy while taking this medication and for 1 month after treatment. Female patients must use reliable birth control during treatment and for 1 month after the last dose. Ask your doctor which forms of birth control to use while taking this medication. Female patients must take a pregnancy test before starting treatment. If you become pregnant or think you may be pregnant, tell your doctor right away.

To receive bosentan in the United States, you must understand, agree to, and carefully follow the requirements of the REMS Program for this medication. If you live in Canada or any other country, consult your doctor and pharmacist for your country's regulations.

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.

A product that may interact with this drug is: sparsentan.

Other medications can affect the removal of bosentan from your body, which may affect how bosentan works. Examples include cyclosporine, HIV protease inhibitors (such as atazanavir), among others.

This drug can speed up the removal of other drugs from your body, which may affect how they work. Examples of affected drugs include daridorexant, elacestrant, glyburide, mavacamten, quizartinib, revumenib, among others.

This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist about using a reliable backup birth control method while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep the tablets in the blister package until ready to use. Tablets or half tablets from the open blisters may be stored back in the opened blister for up to 7 days. 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.