Dependence & Withdrawal: Because of its high potency, it carries a severe risk of physical dependence. Stopping chronic use triggers a rapid-onset, intense opioid withdrawal syndrome that requires professional medical detoxification.
... There's a whole ecosystem there and it's pretty fucking hilarious. The raw ingredients are come from China or India mostly, the manufacturers are all over the place, and there's actually a thing going on where no one wants to be the one selling the WIENER BONER MALE VITALITY supplement that doesn't work so they're all at least a little bit overdosed.
I don't have time to look for sources but it's out there. Health Canada has a list of actions they've taken against has station boner pill makers.
I don't know about the other gas station supplements. It's changed a lot since it was sketchy fake weed and ephedrine pills/bath salts.