Sildenafil is a medication that was originally developed to treat angina, a condition that causes chest pain due to reduced blood flow to the heart.
However, during clinical trials, it was discovered that the medication also had a positive effect on erectile dysfunction (ED).
Today, sildenafil is best known for its use in treating ED, but it is also used to treat other conditions, such as pulmonary arterial hypertension (PAH).
What is Pulmonary Arterial Hypertension?
PAH is a chronic and progressive condition that can lead to significant impairment of physical activity and quality of life.
It affects the blood vessels in the lungs, causing high blood pressure in the pulmonary artery.
This increased pressure can cause the right side of the heart to work harder, leading to enlargement and eventually heart failure.
PAH is a rare condition, with an estimated prevalence of 15 to 50 cases per million adults in the general population.
There are several types of PAH, including idiopathic PAH, heritable PAH, and PAH associated with other medical conditions, such as connective tissue diseases or congenital heart defects.
Diagnosis typically involves a comprehensive evaluation of symptoms, medical history, physical examination, and diagnostic tests, such as echocardiography, right heart catheterization, and pulmonary function tests.
How Sildenafil Works for PAH
In addition to its role in treating ED, sildenafil has been shown to be effective in treating PAH by improving the function of the pulmonary artery and reducing blood pressure in the lungs.
When taken orally, sildenafil is rapidly absorbed and reaches peak plasma concentrations within one hour.
It is then metabolized in the liver and excreted from the body through the kidneys and feces.
Sildenafil works by inhibiting the action of PDE5, an enzyme that breaks down cyclic guanosine monophosphate (cGMP), a signaling molecule that relaxes smooth muscle cells in the blood vessels.
By inhibiting PDE5, sildenafil increases the levels of cGMP, which causes the smooth muscle cells in the pulmonary artery to relax and the blood vessels to dilate, reducing the resistance to blood flow and improving oxygenation.

Effectiveness of Sildenafil in Treating PAH
Clinical studies have shown that sildenafil is an effective treatment option for PAH.
In a randomized, double-blind, placebo-controlled trial involving 278 patients with PAH, sildenafil improved exercise capacity, quality of life, and hemodynamics.
Another study showed that sildenafil was effective in treating PAH in children, with no serious adverse effects reported.
However, it’s important to note that the efficacy of sildenafil may vary depending on the type and severity of PAH, as well as individual factors, such as age, sex, and medical history. Some patients may not respond to sildenafil, or may require higher doses or combination therapy with other medications to achieve optimal outcomes.
Side Effects of Sildenafil in PAH Treatment
Like all medications, sildenafil can cause side effects, and some of these side effects may be more common or severe in patients with PAH.
The most common side effects of sildenafil include headache, flushing, and indigestion.
Other side effects may include vision changes, such as blurred vision or sensitivity to light, and a stuffy or runny nose. In rare cases, sildenafil may cause more serious side effects, such as sudden hearing loss or a sudden decrease in vision.
It’s important to talk to your healthcare provider about the potential benefits and risks of sildenafil, and to report any side effects or adverse reactions promptly. In some cases, dose adjustments or discontinuation of the medication may be necessary to manage side effects.
Choosing Sildenafil for PAH Treatment
If you have been diagnosed with PAH, your healthcare provider may recommend sildenafil as a treatment option. However, there are several factors to consider when choosing sildenafil or other medications for PAH treatment, such as the severity and type of PAH, medical history, age, and other individual factors.
It’s important to work closely with your healthcare provider to determine the best treatment plan for your needs.
When considering sildenafil, your healthcare provider will evaluate your medical history and perform a comprehensive physical exam and diagnostic tests to determine if sildenafil is a safe and effective treatment option for you. They may also consider other factors, such as your age, sex, and other medical conditions, when determining the optimal dose and duration of treatment.
It’s important to follow your healthcare provider’s instructions carefully when taking sildenafil for PAH. Always take the medication as prescribed and do not exceed the recommended dose. Be sure to report any side effects or adverse reactions promptly, and to inform your healthcare provider of any other medications or supplements you may be taking.
Conclusion
Sildenafil is a medication that is commonly used to treat erectile dysfunction, but it is also an effective treatment option for pulmonary arterial hypertension.
By inhibiting the action of PDE5, sildenafil can improve blood flow and reduce blood pressure in the pulmonary artery, which can improve symptoms and quality of life for patients with PAH.
While sildenafil is generally well-tolerated, it’s important to talk to your healthcare provider about the potential benefits and risks of the medication, and to discuss any other medical conditions or medications that you may be taking.
If you have been diagnosed with PAH, talk to your healthcare provider about whether sildenafil may be a good treatment option for you.
References, Studies and Sources:
https://www.drugs.com/sildenafil.html
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1994020/
Owner, entrepreneur, and health enthusiast.
Chris is one of the Co-Founders of Pharmacists.org. An entrepreneur at heart, Chris has been building and writing in consumer health for over 10 years. In addition to Pharmacists.org, Chris and his Acme Health LLC Brand Team own and operate Diabetic.org and the USA Rx Pharmacy Discount Card powered by Pharmacists.org.
Chris has a CFA (Chartered Financial Analyst) designation and is a proud member of the American Medical Writer’s Association (AMWA), the International Society for Medical Publication Professionals (ISMPP), the National Association of Science Writers (NASW), the Council of Science Editors, the Author’s Guild, and the Editorial Freelance Association (EFA).
Our growing team of healthcare experts work everyday to create accurate and informative health content in addition to the keeping you up to date on the latest news and research.