Penegra 50 mg contains sildenafil citrate 50 mg, a PDE5 inhibitor used for erectile dysfunction (ED). It can affect blood pressure because sildenafil causes blood vessels to relax and widen (vasodilation), which may lead to a temporary decrease in blood pressure. Why Penegra 50 mg can lower blood pressure Sildenafil increases the effect of nitric oxide, a natural chemical that relaxes blood vessel walls. Relaxed blood vessels allow blood to flow more easily, which can slightly reduce blood pressure. In most healthy users, this change is usually mild and temporary. When blood pressure effects may be stronger The risk of a noticeable blood pressure drop may increase if Penegra 50 mg is taken with: Nitrate medicines (such as nitroglycerin) — this combination can cause a dangerous fall in blood pressure. Alpha-blockers used for blood pressure or prostate problems. Heavy alcohol consumption, which can worsen dizziness or low blood pressure. Other medicines that lower blood pressure. Possible signs of low blood pressure Some people may experience: Dizziness Lightheadedness Fainting Weakness Blurred vision Who should use caution? Talk to a healthcare professional before using Penegra 50 mg if you have: Heart disease Uncontrolled high or low blood pressure Recent heart attack or stroke Severe liver or kidney problems Seek urgent medical help if you develop chest pain, severe dizziness, sudden vision/hearing changes, or an erection lasting more than 4 hours. For many men, 50 mg is a commonly used sildenafil dose, but the safest dose depends on your health, other medicines, and previous response to ED treatments.