Your man may have seen Zac Efron casually popping Viagra in that one movie, but taking an erectile dysfunction pill, especially when he doesn’t need it, won’t necessarily give him stronger or longer erections. And some ED meds, like Cialis, can stay in his system for 36 hours, giving him easy hard-ons the whole time. So unless you’re planning a long weekend away—and filling the trunk exclusively with lube—tell him to nix the Rx. “Popping Viagra when he doesn’t need it is a terrible idea,” says sex therapist Barry Mccarthy, PHD. “Mostly because it reinforces the notion that good sex is totally dependent on his penis.” And since he doesn’t have a problem in that area anyway, you’d be better off spending your time getting it on without the meds.