Skip to main content


Generic name: treprostinil (oral) [ tre-PROS-ti-nil ]
Brand name: Orenitram
Dosage form: oral tablet, extended release (0.125 mg; 0.25 mg; 1 mg; 2.5 mg; 5 mg)
Drug class: Agents for pulmonary hypertension

Medically reviewed by on Aug 22, 2022. Written by Cerner Multum.

What is treprostinil?

Treprostinil dilates (widens) the arteries and decreases the amount of blood clotting platelets in your body. These effects lower blood pressure in the pulmonary artery that leads from the heart to the lungs.

Treprostinil is used to treat pulmonary arterial hypertension (PAH). treprostinil improves your ability to exercise.

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


You should not use treprostinil if you have severe liver disease.

Before taking this medicine

You should not use treprostinil if you are allergic to it, or if you have severe liver disease.

To make sure treprostinil is safe for you, tell your doctor if you have:

It is not known whether treprostinil will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using treprostinil.

It is not known whether treprostinil passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

How should I take treprostinil?

Follow all directions on your prescription label. Your doctor may occasionally change your dose. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Do not crush, chew, or break an extended-release tablet. Swallow it whole. Do not use a broken pill.

Take with food.

Take your doses at regular intervals to keep a steady amount of the drug in your body at all times.

You should not reduce your dose or stop using treprostinil suddenly. Stopping suddenly may make your condition worse.

Tell your doctor if you need to stop taking treprostinil for any reason. You may need an alternate treatment during that time.

Treprostinil is made with a shell that is not absorbed or melted in the body. Part of the tablet shell may appear in your stool. This is a normal side effect of treprostinil and will not make the medication less effective.

Call your doctor if you have new or worsening PAH symptoms such as feeling short of breath (even with mild exertion), tiredness, chest pain, and pale skin.

Use treprostinil regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely. You will probably have to use this medicine for several months or years to control your condition and keep it from getting worse.

Store at room temperature away from moisture and heat.

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.

Call your doctor if you miss 2 or more doses of treprostinil.

What happens if I overdose?

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

What should I avoid while taking treprostinil?

Do not drink alcohol. Alcohol can cause the tablet to release treprostinil too quickly.

Treprostinil side effects

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

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

  • severe headache;

  • vomiting; or

  • a light-headed feeling, like you might pass out.

Common side effects of treprostinil may include:

  • headache;

  • pain in your arms or legs;

  • diarrhea, nausea; or

  • flushing (warmth, redness, or tingly feeling).

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.

What other drugs will affect treprostinil?

Tell your doctor about all your current medicines and any you start or stop using, especially:

This list is not complete. Other drugs may interact with treprostinil, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.