Important Safety Information Full Prescribing Information Patient Package Insert Instructions For Use

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Causes and Symptoms of PAH


Some known causes of pulmonary arterial hypertension (PAH) include:

  • Family history of PAH (familial or heritable PAH)
  • Heart disease
  • HIV
  • Certain prescription diet medications
  • Certain illegal drugs such as cocaine, amphetamines,
    and methamphetamines
  • Connective tissue disease, such as scleroderma
  • Liver disease

In idiopathic PAH, no cause can be identified.


The following are symptoms that you may discuss with your doctor:

  • Dizziness and/or fainting (syncope)
  • Shortness of breath (dyspnea)
  • Chest pain (angina)
  • Feeling tired or worn out (fatigue)
  • Swollen ankles and legs (edema)
  • Swollen abdomen (ascites)
  • Rapid, hard, or irregular heartbeats (palpitations)


As the disease worsens, its symptoms may limit all physical activity, or even take place during rest.


Tyvaso is a prescription medicine used in adults to treat pulmonary arterial hypertension (PAH) (WHO Group 1), which is high blood pressure in the arteries of your lungs. Tyvaso can improve exercise ability in people who also take bosentan (an endothelin receptor antagonist) or sildenafil (a phosphodiesterase-5 inhibitor). The effects decrease over 4 hours; treatment timing can be adjusted for planned activities.

Studies establishing effectiveness included predominately patients with NYHA Functional Class III symptoms and etiologies of idiopathic or heritable PAH (56%) or PAH associated with connective tissue diseases (33%).

Important Safety Information for Tyvaso

  • Tyvaso is breathed in (inhalable) through your mouth into your lungs. Tyvaso should only be used with the Tyvaso Inhalation System
  • The effects of Tyvaso are unknown in patients with lung disease (such as asthma or chronic obstructive pulmonary disease) and in patients under 18 years of age
  • If you have low blood pressure, Tyvaso may cause symptomatic hypotension (low blood pressure)
  • Because Tyvaso reduces the ability of your blood to clot (coagulate), it may increase your risk for bleeding if you are taking blood thinners (anticoagulants), such as warfarin or heparin
  • The use of Tyvaso with diuretics (water pills), antihypertensives (medications used to treat high blood pressure or heart disease), or other vasodilators (medications that lower blood pressure) may increase your risk for hypotension (low blood pressure)

Other medical conditions and medicines may affect your use of Tyvaso by increasing the risk of side effects or decreasing effectiveness. It is important to tell your doctor about your medical conditions and any medicines you may be taking, including:

  • If you are taking gemfibrozil (for high cholesterol) or rifampin (for infection), your Tyvaso dosage may need adjustment
  • If you have liver or kidney problems, your ability to tolerate Tyvaso may be affected
  • If you are pregnant, breast-feeding, or planning to become pregnant, talk with your healthcare provider about whether you should take Tyvaso

The most common side effects of Tyvaso are coughing, headache, throat irritation and pain, nausea, reddening of the face and neck (flushing), and fainting or loss of consciousness. These are not all the possible side effects of Tyvaso. Tell your doctor about any side effects that bother you or do not go away. Your doctor may be able to help you manage the side effects.

For more information about Tyvaso, please see the Full Prescribing Information, Patient Package Insert, and the Tyvaso Inhalation System Instructions for Use Manual. Questions? Call the Customer Service Line at 1-877-UNITHER (1-877-864-8437).

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