Sildisoft Tablets contain sildenafil citrate, a medicine used to treat erectile dysfunction (ED) in men. Like all medicines, it can cause side effects, although not everyone gets them. Common side effects reported with Sildisoft include headache, facial flushing (warmth of face or neck), nasal congestion or runny nose, indigestion, dizziness, nausea and mild vision changes (like blurred or tinted vision). These are usually mild and go away as your body adjusts. Less common but more serious side effects can occur and need immediate medical help if they appear. These include prolonged and painful erection lasting more than 4 hours (priapism), sudden loss of vision or hearing, chest pain, irregular heartbeat, fainting, or severe allergic reactions. Sildisoft can also interact with certain drugs (especially nitrates and some blood pressure medications), which can dangerously lower blood pressure. Always take it only under medical guidance and tell your doctor about any health conditions or other medicines you are taking.