The benadryl myth of recharging receptors is pure bullshit. It makes you groggy, which if anything, counteracts the the stim effects of the clen.
I'm leery of giving advice on clen use to anyone because you never know what their tolerance might be. Wheneber I have a client who wants to use it, I'll simply say what the typical dosages are and let them make their own decisions. I'd never recommend it or suggest a cycle. Some are okay with it, others won't react so well. Some are fine for a while, and then it takes a bad turn. We have to be honest about this. Clen can be dangerous, just ask Guardian. Oh wait, you can't.