I suffer from constipation and when I mixed this with pea the constipation was very bad I am now consuming natural yoghurt everyday day morning and evening. Have googled the side effects but constipation is not mentioned, however this is what happened to me. I also take Tadalafil 5mg every other day I admit combined with L-Arginine the results are slightly more improved but its never been a “oh my god I need to take this” kind of supplement!!!!! For me its effects are subtle there but not in your face. I am trying to cycle this may help with the side effects.