Treating PAH

The understanding of pulmonary arterial hypertension (PAH) and the number of available treatment options has grown over the past 2 decades. PAH-specific treatment has advanced from 1 FDA-approved treatment in 1995 to 12 FDA-approved treatment options available today, with many more in clinical development.

Treatment pathways

There are 3 substances in the body that become imbalanced in people with PAH: prostacyclin, endothelin, and nitric oxide. These substances need to be in balance to help keep blood vessels in the lungs open and working properly. Currently there are 4 approved types of PAH treatment that work on these different pathways to increase or decrease the various substances to open up the blood vessels.

PDE-5 inhibitor=phosphodiesterase type 5 inhibitor.

sGC stimulator=soluble guanylate cyclase stimulator.

ERA=endothelin receptor antagonist.

Because these treatments work on different pathways to help keep blood vessels in the lungs open, your doctor may prescribe more than one type of treatment.

Prostacyclin class therapy

Prostacyclin is a substance that is naturally present in the body and helps keep blood vessels open and working properly. People with PAH often have lower levels of this substance. Prostacyclin class therapies mimic some of the effects of the natural prostacyclin that is missing.

Current guidelines suggest prostacyclin class therapy should be considered for patients in Functional Class III or IV. Talk to your doctor to see if you could benefit from prostacyclin class therapy.

Next: Get Answers to Frequently Asked Questions About PAH


Before you take Tyvaso, tell your healthcare provider about all of your medical conditions, including if you:

It is important to tell your healthcare provider about all the medicines you may be taking, including prescription and non-prescription medicines, vitamins, and herbal supplements, as they may affect your use of Tyvaso by increasing the risk of side effects or decreasing effectiveness. Especially tell your healthcare provider if you take any of these medicines:

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 healthcare provider about any side effects that bother you or do not go away. Your healthcare provider may be able to help you manage the side effects.


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, (ERA)) or sildenafil (a phosphodiesterase-5 (PDE-5) inhibitor). Your ability to do exercise decreases 4 hours after taking Tyvaso.

The effects of Tyvaso are unknown in patients under 18 years of age.


Please see the Full Prescribing Information, Patient Package Insert, and the Tyvaso Inhalation System Instructions for Use manual.

For additional information about Tyvaso, visit or call 1-877-UNITHER (1-877-864- 8437).

Call your healthcare provider for medical advice about side effects. You may report side effects to the FDA at or call 1-800-FDA-1088.

This information is provided for an informational purpose and is not intended as treatment advice. Patients should consult a healthcare professional for treatment advice.