In the U.S.—

• Antihypertensive (pulmonary)
• vasodilator

Treprostinil (treh-PROST-tin-il) belongs to a group of agents called prostaglandins. Prostaglandins occur naturally in the body and are involved in many biological functions. Treprostinil is used to treat the symptoms of primary pulmonary hypertension, or the high blood pressure that occurs in the main artery that carries blood from the right side of the heart (the ventricle) to the lungs. When the smaller blood vessels in the lungs become more resistant to blood flow, the right ventricle must work harder to pump enough blood through the lungs. Treprostinil works by relaxing blood vessels and increasing the supply of blood to the lungs, reducing the workload of the heart.

This medicine is available only with your doctor's prescription, in the following dosage form(s):

Parenteral
• Injection (U.S.)

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For treprostinil, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to treprostinil. Also tell your doctor and pharmacist if you are allergic to any other substances, such as, [foods, preservatives, or dyes].

Pregnancy—Treprostinil has not been studied in pregnant women and, although treprostinil has not been shown to cause birth defects or other problems in animals, it is only recommended for use in pregnant women when necessary. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether treprostinil passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of treprostinil in children with other age groups.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of treprostinil in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking treprostinil, it is especially important that your doctor and pharmacist know if you are taking any of the following:

• Anticoagulants (blood thinners such as warfarin [Coumadin])—Use with treprostinil may increase the risk of bleeding

• Antihypertensives (medicine for high blood pressure), or
• Diuretics (water pills), or
• Vasodilators (e.g., Hydralazine [Apresoline])—Effects on blood pressure may be increased

• Liver disease—Treprostinil effects may increase because of slower removal of medicine from the body

Your doctor or nurse will teach you how to prepare the medicine and use the pump for administering the medicine. Treprostinil must be administered continuously by a portable pump that is operated by a small computer. The medicine will be delivered directly under your skin through a catheter.

The instructions for the use of the pump may vary depending on the particular make and model of the pump. Your doctor or nurse will give you detailed instructions on how to use and care for the particular pump and accessories that you will use for administering your medicine.

Dosing—

The dose of treprostinil will be different for different patients and will be determined by your doctor. The amount of medicine you take may have to be increased gradually by your doctor. It must never be stopped suddenly. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of treprostinil. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the concentration of the medicine and the rate at which the infusion pump delivers the medicine.

• For injection dosage form:
  • For pulmonary arterial hypertension:
    • Adults—Initially, 1.25 nanograms per kilogram (kg) (0.6 nanogram per pound) of body weight per minute. Your doctor may increase or decrease your dose as necessary.
    • Children—Use and dose must be determined by your doctor.

Missed dose—

Treprostinil has to be administered by a continuous intravenous infusion and it must never be stopped suddenly.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• If the medicine has particles in it or is discolored, it should be discarded.
• Do not keep outdated medicine, or medicine no longer needed. Ask your health care professional how you should dispose of any medicine you do not use. Be sure that any discarded medicine is out of the reach of children.

It is important that your doctor check your progress at regular visits. This will allow your doctor to make sure the medicine is working properly and to change the dosage if needed.

Be sure to report any signs of infection or reaction at the catheter site to your doctor. Also, if you develop a sudden fever, contact your doctor as soon as possible.

Avoid the use of saunas, hot baths, or sunbathing, or other situations that may cause blood vessels to dilate, resulting in low blood pressure and increasing the possibility of dizziness, light-headedness, or fainting.

Do not suddenly stop using this medicine. Stopping suddenly may bring on symptoms of your condition and can be dangerous. Check with your doctor before stopping completely.

Your doctor may want you to carry a medical identification card stating that you are using this medicine.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

• More common
  • Edema, such as, swelling;  infusion site reaction, such as, accumulation of blood at site of injection; dry, red, hot, or irritated skin; hardening of site of injection;  vasodilation, such as, feeling of warmth or heat, flushing or redness of skin, especially on face and neck, feeling faint, dizzy, or light-headed 
  
  

• Less common
  • Hypotension, such as, blurred vision, confusion, dizziness, faintness, lightheadedness when getting up from a lying or sitting position, sudden sweating, unusual tiredness or weakness 
  
  

• Symptoms of Overdose

  Get emergency help immediately if any of the following symptoms of overdose occur

  • Diarrhea;  flushing, such as, feeling of warmth and redness of the face, neck, arms, and occasionally, upper chest ;  headache;  nausea and vomiting  
  
  

• hypotension, such as, blurred vision, confusion, dizziness, faintness, lightheadedness when getting up from a lying or sitting position, sudden sweating, unusual tiredness or weakness 

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome.

• More Common
  • Diarrhea;  dizziness;  headache;  infusion site pain;  jaw pain;  nausea;  pruritus, such as, itching skin;  rash 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.