Vilitra 40 mg should not be taken with nitrate medications because the combination may cause a dangerous drop in blood pressure. Men with heart conditions, low blood pressure, liver or kidney problems, or those using other medicines should consult a healthcare provider before use. Possible side effects may include headache, facial flushing, dizziness, nasal congestion, indigestion, and temporary vision changes. Higher doses may increase the likelihood of side effects. Serious symptoms, such as chest pain, sudden vision or hearing changes, fainting, or an erection lasting longer than four hours, require immediate medical attention.