Caber is made as a dopamine antagonist so can be used anytime for such purposes (and I have), BUT, the question is why?
If you're not combating prolactin/dopamine balance-induced activity from steroids, it's so potent that you risk decimating your prolactin levels. And that's just as bad as having no E2. Having zero prolactin is not a good thing, you NEED some of it to balance dopamine, so you don't want it to go too low.
Secondly, again, if you're not using steroids, you risk a lot of the sides that come along with Caber use (sleepiness, fatigue and nausea are big) for no real benefit other than staying hard after you finish. It does work, but it's not worth it just for that IMO.
The natural supp Mucuna Pruriens (L-Dopa) also has dopamine antagonist potential. Taking that with a glass full of Pomegranate juice (same deal) pretty much has the same effect on refractory on demand. But it won't work every time, as soon as your body acclimatizes to it. Your body is ridiculously adaptable and resilient to dopamigenic activity - how addictions start.