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Treprostinil Injection

pronounced as (tre pros' ti nil)

Why is this medication prescribed?

Treprostinil injection 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 injection is also used to treat PAH when another medication (epoprostenol) did not help or could not be tolerated. 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 and platelet-aggregation inhibitors. It works by relaxing the blood vessels, including those in the lungs, and improving blood flow.

How should this medicine be used?

Treprostinil injection comes as a solution (liquid) to be continuously injected subcutaneously (under the skin). Treprostinil injection is usually used with an external subcutaneous infusion pump for continuous delivery of the medication. Treprostinil injection may also be given as a continuous intravenous (into a vein) infusion. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use treprostinil injection exactly as directed. Do not inject more or less of it or take it more often than prescribed by your doctor.

Before you use treprostinil injection for the first time, your doctor or nurse will show you how to use the external infusion pump to receive your medication. Read the written instructions that come with the pump and the medication. Be sure that you understand these directions. Ask your healthcare provider if you have any questions about how to infuse treprostinil injection.

Your doctor will probably start you on a low dose of treprostinil and gradually increase your dose, not more than once every week. Your doctor may need to slow down your infusion or interrupt your treatment if you experience certain side effects. It is important for you to tell your doctor how you are feeling during your treatment with treprostinil injection.

Treprostinil may control the symptoms of PAH but does not cure it. Do not stop using treprostinil injection without talking to your doctor. If you suddenly stop using treprostinil, your symptoms may get worse. Your doctor will probably decrease your dose gradually.

Treprostinil injection is not available in pharmacies. You can only get treprostinil from a specialty pharmacy. Ask your doctor if you have any questions about receiving your medication.

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 using treprostinil injection,

  • tell your doctor and pharmacist if you are allergic to treprostinil (Orenitram, Remodulin, Tyvaso), any other medications, or any of the ingredients in treprostinil injection. 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: gemfibrozil (Lopid), medications for high blood pressure, 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 low blood pressure, bleeding problems, or liver problems.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving treprostinil injection, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving treprostinil injection.

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?

Call your doctor to ask what to do if the infusion of treprostinil injection is stopped for any reason.

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
  • swelling of arms, hands, feet, ankles or lower legs
  • restlessness
  • rash

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately:

  • pain, redness, rash, and swelling at infusion site
  • fever, chills, or other signs of infection
  • unusual bleeding or bruising
  • dizziness or fainting

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

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

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

Your healthcare provider will tell you how to store your medication. Store your medication only as directed. Make sure you understand how to store your medication properly.

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
  • flushing

What other information should I know?

Keep all appointments with your doctor.

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

  • Remodulin®
Last Revised - 04/15/2023