Suhagra 50 mg (which contains sildenafil citrate, a PDE5 inhibitor used for erectile dysfunction) can cause nasal congestion in some people. Sildenafil works by relaxing blood vessels and increasing blood flow, mainly to help achieve and maintain an erection. However, this same blood vessel–relaxing effect can also occur in other parts of the body, including the nasal lining. When blood vessels inside the nose widen, the nasal tissues can become slightly swollen, leading to a stuffy or blocked nose, commonly referred to as nasal congestion. This side effect is generally mild and temporary, and it tends to appear within a few hours of taking the tablet. Not everyone experiences it, but it is considered a fairly common side effect of sildenafil and other similar medications. Along with nasal congestion, some users may also notice other related effects such as headache, facial flushing, dizziness, or mild sinus pressure. These usually resolve on their own as the drug wears off.