Managing Interstitial Lung Disease With Pulmonary Hypertension: What to Know About Tyvaso

Written by Patricia Weiser, PharmD
Medically Reviewed by Beth Johnston, BCPS, PharmD on February 17, 2026

Interstitial lung disease (ILD) refers to a group of conditions that cause damage and stiffness in the lung tissue. Over time, this damage can make it harder for oxygen to move into the bloodstream. In some people with ILD, pressure also builds up in the blood vessels of the lungs. This is called pulmonary hypertension (PH).

Pulmonary hypertension with interstitial lung disease (PH-ILD) is a condition where high blood pressure develops in the lungs because of underlying lung scarring or inflammation. 

Symptoms of PH-ILD often include shortness of breath, tiredness, and reduced ability to be physically active. Treatment often focuses on managing the underlying lung disease and supportive care measures, such as oxygen therapy.

Tyvaso (treprostinil) is a treatment option specifically approved for PH-ILD. It is an inhaled medicine that is typically used four times per day. Below are common questions and answers about Tyvaso for PH-ILD.

Tyvaso contains the active medicine treprostinil, which mimics the effect of a natural substance in your body called prostacyclin. It helps blood vessels relax and widen. It also helps prevent platelets (a type of blood cell) from clumping together. This can make it easier for your heart to pump blood to your lungs.

To decide if Tyvaso is right for you, your health care provider will review your medical history, including your lung condition, the type of pulmonary hypertension (PH) you have, your symptoms, and your overall health. 

Tyvaso is FDA-approved for adults with PH-ILD. Before prescribing Tyvaso, your health care provider may do tests to confirm that you have PH-ILD, including a procedure to directly measure the pressure in the lungs.

Tyvaso is not a cure for PH-ILD, but it can help increase exercise capacity in some people. Talk with your health care provider to see if Tyvaso may be an option for you.

A 16-week clinical study called INCREASE was done to test how well inhaled Tyvaso works to improve the ability to exercise in adults with confirmed PH-ILD. To join the study, participants needed to be able to walk at least 100 meters during a six-minute walk test. If they were taking medicines for their underlying lung disease, they had to be on the same dose for at least 30 days before entering the study.

People could not join if they had pulmonary hypertension from another cause, such as other health conditions (such as serious heart problems or lung infection) or recent use of certain treatments. These rules helped ensure the study focused specifically on people with PH-ILD.

Participants were randomly assigned to use either Tyvaso or a placebo (an inhaled treatment with no active medicine) four times a day for 16 weeks. Neither the participants nor the researchers knew who was receiving Tyvaso. Participants had a checkup visit every four weeks to see how they were doing and to measure their walking distance.

The study included 326 adults with different types of interstitial lung disease. The most common types were interstitial pneumonia of unknown cause (45%), combined pulmonary fibrosis and emphysema (about 25%), and connective tissue disease (22%). At the start of the study: 

  • The average age of participants was about 66 years.
  • Nearly half (47%) were female, and the rest were male.
  • The average six-minute walk distance was about 260 meters. 
  • Most (73%) were White, 22% were Black or African American, 4% were Asian, 1% were American Indian or Alaskan Native, and the rest identified as unknown or multiple races.
  • Around 8% were Hispanic or Latino, and the rest were not Hispanic or Latino or had missing ethnicity information.
  • Most (72%) were using oxygen therapy.

The main goal of the study was to see how much the six-minute walk distance changed after 16 weeks, measured between 10 and 60 minutes after a dose. Researchers then compared how much the walking distance changed from the start of the study between the two groups.

The main results of the INCREASE study showed that Tyvaso improved exercise ability in people with PH-ILD. 

At week 16, people using Tyvaso walked about 31 meters farther on average in six minutes than those using a placebo. The walking distance was measured when the medicine was working at its strongest, between 10 and 60 minutes after a dose. This is when Tyvaso reaches its highest level in the body (also called peak effect).

The researchers also looked at other outcomes, such as average walking distance at different timepoints and how long it took for a person’s condition to get worse. Worsening was defined as having to stay in the hospital for heart or lung problems, a major decline in walking ability, a lung transplant, or death from any cause. Some of the other results were as follows.

  • At week 12, people using Tyvaso walked about 31 meters farther than those using a placebo.
  • At week 15, people using Tyvaso walked about 22 meters farther than those using a placebo when walking distance was measured at least four hours after a dose. This is when the medicine is at its lowest level in the body (also called the trough effect). 
  • About 23% of people using Tyvaso experienced worsening of their condition, compared with about 33% of those using a placebo.

Individual results may differ from what was seen in the study.

Response can vary from person to person. Some people may notice changes sooner than others. In the INCREASE study, some improvements in walking distance were seen as early as one to two months after starting Tyvaso. The biggest improvements were seen after three to four months of use.

It’s important to understand that Tyvaso reaches its maximum effect about 10-60 minutes after you inhale a dose. Tyvaso doses are usually spaced about four hours apart, and the effects gradually decrease before the next dose is due. This means you may want to plan your treatment around your activities. For example, you might schedule a dose of Tyvaso right before exercise, errands, or social events so the medicine is working at its strongest when you need it most.

Your health care provider can help you decide how to time your doses. They will also track your progress over time to see how well the treatment is working for you.

Most people tolerate Tyvaso well. But, as with most medicines, side effects are possible. Many can be prevented or managed with careful monitoring and by knowing when to contact your health care provider. 

Some common side effects of Tyvaso are cough, throat pain or irritation, headache, nausea and other stomach-related effects, dizziness, reddening of the face and neck (flushing), and fainting.

Using Tyvaso properly may help lower the chance of throat discomfort. Review your technique with your care team and follow the steps in the Instructions for Use that comes with your medicine.

Your health care provider may suggest ways to prevent or manage throat irritation, such as drinking some cold water or hot tea before using Tyvaso. Or you may want to try using an over-the-counter (OTC) sore throat spray or lozenge to numb your throat before a dose. 

This is not a complete list of Tyvaso side effects. Tell your health care provider if side effects feel severe, worsen, or do not improve.

Both Tyvaso and Tyvaso dry powder inhaler (DPI) contain the same active medicine (treprostinil) and are used to treat the same conditions. The main difference is how the medicine is delivered:

  • Tyvaso is a liquid that is inhaled using a nebulizer device, which is a small machine that turns the liquid into a mist you inhale. Tyvaso nebulizer treatments require preparation, setup, and cleaning. It usually takes about two to three minutes to inhale each dose.
  • Tyvaso DPI is a dry powder inhaled using a small, handheld inhaler. The DPI device is smaller and does not require charging or cleaning. It usually takes one to two seconds to inhale each dose. 

A study was done to see whether people could safely switch from the Tyvaso nebulizer to Tyvaso DPI and how satisfied they were with the change. The study included people who had been using Tyvaso nebulizer treatment for at least three months, then switched to Tyvaso DPI. After three weeks, the results showed that switching to Tyvaso DPI was safe and well-tolerated. Most people were highly satisfied and chose to continue using the DPI.

You and your health care provider can decide which option is best for you based on your needs and preferences.

Financial support options, including Tyvaso copay and patient assistance programs, are available from United Therapeutics Cares. For more information, visit this website or call 844-864-8437.

 

 

 

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