Husband has low libido. :(

I have a high libido and he has a low one. We definitely couldn't wait to have sex (but actually did). But once we had, his libido basically was shot. Everything works and we're happy when we do it but it's so seldom. I've tried to explain to him that we really need to do it while TTC. He says he will go to the dr if nothing over the counter works. Anyone have any ideas for me?