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pronounced as (tre pros' ti nil)

Why is this medication prescribed?

Treprostinil is used to treat certain kinds of pulmonary arterial hypertension (PAH; high blood pressure in the vessels carrying blood to the lungs, causing shortness of breath, dizziness, and tiredness). Treprostinil may improve the ability to exercise and slow the worsening of symptoms in patients with PAH. Treprostinil is in a class of medications called vasodilators. It works by relaxing the blood vessels, including those in the lungs, and improving blood flow.

How should this medicine be used?

Treprostinil comes as extended-release (long acting) tablets to take by mouth. It is usually taken with food 2 times a day (every 12 hours) or 3 times a day (every 8 hours). Take treprostinil at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take treprostinil exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them.

Your doctor will probably start you on a low dose of treprostinil and gradually increase your dose, not more than once every 3 or 4 days. Your doctor may decrease your dose if you experience side effects.

Treprostinil may control the symptoms of PAH but does not cure it. Continue to take treprostinil even if you feel well. Do not stop taking treprostinil without talking to your doctor. If you suddenly stop taking treprostinil, your symptoms may get worse. Your doctor will probably decrease your dose gradually.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking treprostinil,

  • tell your doctor and pharmacist if you are allergic to treprostinil (Orenitram, Remodulin, Tyvaso), any other medications, or any of the ingredients in treprostinil tablets. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: other medications that contain treprostinil (Remodulin, Tyvaso), gemfibrozil (Lopid), or rifampin (Rifadin, Rimactane). Many other medications may also interact with treprostinil, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
  • tell your doctor if you have liver problems. Your doctor may tell you not to take treprostinil.
  • tell your doctor if you have or have ever had diverticulosis (small pouches in the lining of the large intestine that can become inflamed).
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking treprostinil, call your doctor.

What special dietary instructions should I follow?

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

What should I do if I forget a dose?

Take the missed dose as soon as you remember it with food. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

If you miss 2 or more doses, talk to your doctor before starting to take it again. You will probably have to restart taking it at a lower dose initially.

What side effects can this medication cause?

Treprostinil may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • diarrhea
  • nausea
  • vomiting
  • flushing
  • jaw pain
  • pain in arms or legs
  • stomach pain

Treprostinil may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

What should I know about storage and disposal of this medication?

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).

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.

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 ( for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • headache
  • nausea
  • vomiting
  • diarrhea
  • dizziness or fainting

What other information should I know?

Keep all appointments with your doctor.

The extended-release tablet does not dissolve in the stomach after swallowing. It slowly releases the medicine as it passes through your digestive system. You may notice the tablet shell in your stool. This is normal and does not mean that you did not receive the full dose of medication.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

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.

Brand names

  • Orenitram®

Other names

  • Treprostinil diolamine
Last Revised - 04/15/2023