What is Adempas Used to Treat?

October 8, 2025 •

3 min read

First approved by the FDA in 2013, Adempas (riociguat) is a unique medication that was the first in a new class of drugs for pulmonary hypertension. It is prescribed to treat two specific types of pulmonary hypertension in adults, and for pediatric patients of a certain weight with pulmonary arterial hypertension (PAH).

Quick Summary

Adempas (riociguat) treats adults with chronic thromboembolic pulmonary hypertension (CTEPH) and pulmonary arterial hypertension (PAH). It improves exercise capacity and functional class by relaxing blood vessels in the lungs.

Key Points

CTEPH Treatment: Adempas treats adults with inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH), improving exercise capacity and functional class.
PAH Treatment: It is indicated for treating adults and certain pediatric patients with pulmonary arterial hypertension (PAH) to improve exercise capacity and delay clinical worsening.
Soluble Guanylate Cyclase Stimulator: Adempas, an sGC stimulator, relaxes pulmonary blood vessels, reducing pressure and improving blood flow.
Black Box Warning for Pregnancy: Due to severe birth defect risks, Adempas has a boxed warning and is contraindicated in pregnant females.
Mandatory REMS Program: Female patients who can become pregnant must enroll in a restricted program requiring monthly pregnancy testing and contraception.
Avoid Nitrates and PDE-5 Inhibitors: Do not use with nitrates, nitric oxide donors, or certain PDE-5 inhibitors due to severe hypotension risk.
Common Side Effects: Common adverse effects include headache, dizziness, upset stomach, and low blood pressure.

Understanding the Primary Indications for Adempas

Adempas, with the active ingredient riociguat, is a prescription medication primarily used to manage two serious forms of high blood pressure in the arteries of the lungs. The active substance, riociguat, belongs to a novel class of drugs known as soluble guanylate cyclase (sGC) stimulators.

Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

For adult patients with CTEPH (classified as WHO Group 4), Adempas is indicated for inoperable CTEPH or persistent/recurrent CTEPH after surgery (pulmonary thromboendarterectomy). It aims to improve exercise capacity and the World Health Organization (WHO) functional class.

Pulmonary Arterial Hypertension (PAH)

Adempas is also used to treat adults and some pediatric patients with PAH (classified as WHO Group 1). Its purpose is to improve exercise capacity, improve WHO functional class, and delay clinical worsening in patients with idiopathic, heritable, or connective tissue disease-associated PAH. It can be used alone or with other PAH medications.

Mechanism of Action: How Adempas Works

Adempas, as an sGC stimulator, works by enhancing the production of cyclic guanosine monophosphate (cGMP) in the blood vessels, leading to relaxation and widening, particularly in the lungs. It achieves this through a dual mechanism: sensitizing sGC to nitric oxide (NO) and directly stimulating sGC independently of NO. This results in reduced pulmonary pressure and improved blood flow, helping to alleviate symptoms and increase exercise capacity.

Potential Risks and Contraindications

Several significant risks and contraindications are associated with Adempas:

Embryo-Fetal Toxicity: Adempas has a black box warning due to the severe risk of harm to a fetus. A mandatory REMS program requires pregnancy testing and contraception for female patients.
Drug Interactions: Avoid taking Adempas with nitrates, nitric oxide donors, or certain phosphodiesterase (PDE-5) inhibitors (like sildenafil and tadalafil) due to the risk of dangerously low blood pressure.
Pulmonary Veno-Occlusive Disease (PVOD): Not recommended for PVOD patients as it can worsen their condition.
Other Contraindications: Should not be used for pulmonary hypertension associated with idiopathic interstitial pneumonias (PH-IIP).

Common Side Effects

Common side effects observed in clinical trials include headache, indigestion, dizziness, nausea, vomiting, diarrhea, hypotension, anemia, peripheral edema, and constipation.

Comparison of Adempas vs. PDE-5 Inhibitors

Adempas and PDE-5 inhibitors like sildenafil are different classes of drugs for PAH.


Feature	Adempas (Riociguat)	PDE-5 Inhibitors (e.g., Sildenafil)
Drug Class	Soluble Guanylate Cyclase (sGC) Stimulator	Phosphodiesterase-5 (PDE-5) Inhibitor
Mechanism	Dual action: Sensitizes sGC to NO and directly stimulates sGC.	Blocks cGMP breakdown, extending NO effects.
Primary Use	CTEPH and PAH.	PAH.
Action	Stimulates pathway regardless of NO levels.	Effective when NO is present.
Clinical Efficacy	Improvements in 6-minute walk distance (6MWD) for CTEPH and PAH.	Improves 6MWD in PAH.
Drug Interaction	Contraindicated with nitrates and PDE-5 inhibitors.	Contraindicated with nitrates.

Conclusion

Adempas is an important treatment for adults with specific forms of pulmonary hypertension, including CTEPH and PAH, and some pediatric PAH patients. Its sGC stimulation mechanism promotes vasodilation and improves blood flow in the lungs, leading to better exercise capacity and functional class. However, prescribers must be vigilant about potential side effects, serious risks like embryo-fetal toxicity requiring a REMS program, contraindications, and drug interactions to ensure safe and effective use. For more detailed information, consult the full prescribing information from the FDA.

Frequently Asked Questions

Adempas is an sGC stimulator with a dual mechanism: sensitizing sGC to NO and directly stimulating it independently of NO. This differs from PDE-5 inhibitors, which only extend the effects of NO.

It's a mandatory restricted distribution program for females due to Adempas's risk of severe birth defects. It requires awareness of the risk, monthly pregnancy testing, and strict contraception.

Adempas can lower blood pressure. If you have pre-existing hypotension, you may be at higher risk for side effects like dizziness. Your doctor will monitor your blood pressure and adjust the dose if needed.

Take your next scheduled dose at the usual time; do not double up. If you miss doses for three or more consecutive days, contact your doctor as a lower starting dose might be required.

Pregnant women, those taking nitrates, nitric oxide donors, or certain PDE-5 inhibitors should not take Adempas. It is also not recommended for patients with PVOD or PH-IIP.

While generally no specific food restrictions exist, taking Adempas with food might help manage indigestion. Avoid aluminum hydroxide or magnesium hydroxide containing antacids within one hour of dosing.

Smoking can affect Adempas metabolism, potentially requiring a higher dose for smokers. If you quit smoking, your doctor will likely need to reduce your dose to avoid higher drug concentrations and potential side effects.