Treprostinil (Orenitram) is a medication used to treat pulmonary arterial hypertension, a type of high blood pressure in the lungs that affects heart function. Orenitram works by relaxing blood vessels in the lungs, which decreases pressure and improves heart function. By improving heart function, it increases exercise ability and delays disease progression.
How it’s administered
Orenitram is available in five strengths:
- White 0.125 mg tablet
- Green 0.25 mg tablet
- Yellow 1 mg tablet
- Pink 2.5 mg tablet
- Red 5 mg tablet
Orenitram is taken two or three times a day, depending on the prescription prescribed. Don’t take two doses at the same time.
Always take this medication with food. Swallow tablets whole. Do not crush, split or chew.
If you miss a dose, take the missed dose with food as soon as possible unless it’s close to the time for the next dose. If it’s close to the time for the next dose, skip the missed dose and go back to the usual time. Don’t take two doses at the same time. Don’t take extra doses.
Medication typically starts at 0.125 mg two or three times a day. It’s increased by 0.125mg every two to four weeks if there are no side effects. There is no known upper dose limit.
Other ways to take treprostinil
- Inhaled treprostinil (Tyvaso).
- Intravenous and subcutaneous treprostinil (Remodulin).
Obtaining oral treprostinil
Oral treprostinil is a limited-distribution medication, which means it can’t be purchased at a local pharmacy. A physician or advanced practice provider who has experience prescribing PH medications must prescribe this medication. The drug is dispensed by mail-order specialty pharmacies determined by your insurance company.
Insurance
You’ll need approval from your insurance company before starting therapy. Most health insurance plans will pay part of the cost of this medication. However, some plans have high out-of-pocket costs. Ask your health insurance provider for information about copay or out-of-pocket costs.
Depending on your insurance type, you might be eligible for assistance from the company that manufactures your medication or a non-profit charitable assistance organization. See PHA’s list of financial assistance resources [www.PHAssociation.org/Help], or call 301-565-3004.
Side effects
- Headache
- Pain in jaw
- Diarrhea
- Pain in arm(s) or leg(s)
- Nausea
- Abdominal discomfort
- Flushing
You might have minor side effects, such as mild flushing or loose stools, all the time.
If you’re dizzy or pass out, your blood pressure might be low. This requires urgent medical attention.
The outside of the pill that contains the medicine doesn’t dissolve in your stomach. You might see small shell in your feces.
Special considerations
Pregnancy and breastfeeding: Limited data exists on the effects of oral treprostinil in pregnant women. Animal reproductive studies with treprostinil diolamine have shown an adverse effect on fetuses. There are no adequate or well-controlled human studies.
It’s unknown whether treprostinil is excreted in human milk or absorbed after ingestion. Because many drugs are excreted in human milk, choose oral treprostinil or breastfeeding.
Pediatrics: Safety and efficacy for pediatric patients hasn’t been established.
Liver disease: Use oral treprostinil with caution if you have mild liver impairment. Avoid taking this if you have moderate liver impairment. Don’t use if you have severe liver disease.
There is increased exposure of treprostinil throughout the body because liver can’t fully clear the medication. Dialysis doesn’t remove oral treprostinil.
Diverticulitis: Ask your doctor about taking this medication if you know you have diverticulosis.
Allergies: Allergies are possible, but unlikely. If you think you might be allergic, please contact your health care provider immediately.
Drug interactions
No medications are prohibited with oral treprostinil.
When oral treprostinil is taken with certain enzyme inhibitors, treprostinil levels can increase throughout the body. Your doctor may reduce your oral treprostinil dosage if you take CYP2C8 enzyme inhibitors (such as gemfibrozil), which interact with liver enzymes that can change drug levels.
Oral treprostinil can be taken with anticoagulants, such as Coumadin. However, oral treprostinil prevents platelets from clumping together to form clots, so taking anticoagulants might increase your risk of bleeding.
Don’t take oral treprostinil with alcohol, which can cause treprostinil to release from the tablet faster than intended. That could cause more side effects.
Discuss all medications with your health care team at every visit.