I myself had some severe stomach problems about 4 years ago and I was a daily smoker. It got pretty bad (puking up blood one morning), so my doctor ran a bunch of tests (ultrasound, upper GI endoscopy, etc). I don't think they ever did a tox screen, and if they did, I never heard about it. I would think that I would have heard about it because as soon as a lot of doctor's find out you partake, they like to start blaming things on that. I think you should be cool, but who knows. I'm just telling you my experience with a similar situation.

As far as smoking, that's up to you. If it were me, I would probably cut back a little, but sometimes, the reefer was the only thing to take my stomach pain away.