Pulmonary Arterial Hypertension
3 medicines
Pulmonary arterial hypertension is raised blood pressure in the lung arteries, treated with targeted medicines that widen the vessels and reduce strain on the heart.
Key facts
- Pulmonary arterial hypertension (PAH) is a rare, serious condition where the small arteries supplying the lungs narrow and stiffen, forcing the right side of the heart to pump against high resistance.
- It is distinct from ordinary high blood pressure and needs treatment aimed at the lung circulation, not general heart and blood pressure management.
- Two targeted drug classes widen the pulmonary arteries: PDE5 inhibitors such as sildenafil relax the vessel walls, and endothelin receptor antagonists such as ambrisentan block a protein that constricts them; patients often use both.
- Early symptoms (breathlessness on exertion, fatigue, light-headedness) are easy to miss, so diagnosis needs specialist testing.
Recognising PAH and how it is managed
Early symptoms are easy to attribute to fitness or age: breathlessness on exertion, fatigue and light-headedness are the most common. As the condition progresses, ankle swelling, chest pain and fainting on effort can develop. Diagnosis requires specialist investigation, typically echocardiography and right-heart catheterisation.
Treatment centres on medicines that dilate the pulmonary arteries and slow disease progression. Sildenafil, a PDE5 inhibitor, relaxes the vessel walls, while ambrisentan, an endothelin receptor antagonist, blocks a protein that makes the arteries constrict and thicken. Patients often use more than one class at once.
When to seek help
Get urgent medical attention if breathlessness suddenly worsens, you faint, or you develop a rapid heart rate at rest. PAH treatment is specialist-led and needs regular review.
This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.
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