sildenafil, an erectile agent. ▪ INDICATIONS: It is used to treat erectile dysfunction. ▪ CONTRAINDICATIONS: Known hypersensitivity to this drug prohibits its use. ▪ ADVERSE EFFECTS: Common side effects include headache, flushing, dizziness, dyspepsia, nasal congestion, urinary tract infection, abnormal vision, diarrhea, and rash.