Bringing up Bipolar?

I have been dating a guy for a little while and he half-joked about being bipolar... which doesn't seem too far off base... How do I bring up that he should seek help, but let him know I will be there for him anyway? -- He knows I've had a lot of experience working with mood disorders, so it's not a big deal to me, but I do feel like he needs someone outside of our relationship to help him. It's a relatively new relationship so I don't want to pressure him, but I know he can be happier.
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+1 y
I did ask if he thinks he has bipolar disorder, (he said yes, he does wonder), and asked if it was clinically diagnosed (no). My question is really, how do you bring up the conversation of "I think you should seek a diagnosis & possible treatment" ?
Bringing up Bipolar?
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