Spedra 50mg Tablets Spedra is a treatment for adult men suffering from erectile dysfunction (also known as impotence). This is when you cannot get, or keep a hard, erect penis suitable for sexual activity. Spedra contains the active substance avanafil. It belongs to a group of medicines called phosphodiesterase type 5 (PDE5) inhibitors & works by helping the blood vessels in your penis to relax. This increases the blood flow into your penis, helping it stay hard & erect when you get sexually excited. Spedra only works if you are sexually stimulated, so you & your partner will still need to use foreplay to get ready for sex, just as you would if you were not taking a medicine to help you.