Hi there, thank you for posting your question on Ehealthforum. This is not intended as a substitute to visiting your own doctor.
Correct me if I'm wrong here, but Veyron-s, just like every other so-called natural herbal "sex enhancer" has never been subjected to any published clinical trial. Therefore we simply do not know if it works or not.
There maybe a reason that you are sensitive to prescription ED meds such as being on other medicines for eg blood pressure.
Dr Andrew Rynne.
www.andrewrynne.com