Avanafil 100 mg is a medication used to treat erectile dysfunction (ED) in men by improving blood flow to the penile tissues. It belongs to the class of phosphodiesterase-5 (PDE-5) inhibitors and works by relaxing blood vessels, allowing increased circulation during sexual stimulation to help achieve and maintain an erection. Avanafil is known for its rapid onset of action, often starting to work within 15–30 minutes, making it a convenient option for many men. The 100 mg dose is commonly prescribed when a moderate strength is required for better effectiveness. Possible side effects may include headache, flushing, nasal congestion, dizziness, and back pain, and it should be taken under proper medical supervision.