The latest news from the erectile dysfunction front is a recently published case study is that the "cuddle hormone" oxytocin, which is linked to emotional bonding between sexual partners and mothers and infants, has been found to have dramatic effects on male libido and erectile capability, at least in some individuals.
Same as Viagra, the discovery of oxytocin's effect on male performance was accidental. The subject described in the case study was given the hormone in a nasal spray to help with social phobia and social difficulties related to Aspberger's syndrome. It helped some with that, but the unexpected payoff was in the bedroom.
His libido improved, going from "very weak" to strong, and his erections and orgasms were better - 46% better, going by a assessment scale someone dreamed up to quantify these things.
However, the treatment was not without its side effects. The man "also hugged a work colleague in a 'very out of character' way."
Since this is only one case, there are still a lot of unanswered questions. Will the hormone work similarly for men without Asperger's? Other research on oxytocin indicates it might, as over 25% of men in an unrelated study experienced improved erections when given oxytocin. Viagra also stimulates oxytocin production, which may account for part of its effect.
Only time will tell how this will pan out, but one of the scientists involved with the discovery and development of Viagra predicts that an oxytocin-based treatment could have 'blockbuster potential'.