From what I read this is like taking a pill and there is training involved. Just like the pill its taken a certain time before having sex. If you don't want to have it, then he doesn't take the injection.
Even without an ED shot, if he has the beginnings of dementia fixating on sex is not an uncommon symptom. There are other posts on this forum from wives with similar issues with their spouses. I would discuss this with his doctor.
Well, don’t. He doesn’t get to act like a studly stud if you’re not in the mood. Leave some sexy magazines in the bathroom and see if that distracts him for a while. I’m not sure what an Ed shot does but I hope the effects don’t last long.
80 year olds who are fixated on sex all the time often suffer from dementia. Has your dh been given a cognitive exam recently?