Most medications leave the stomach after an hour so you should be fine. Additionally, missing one dose of Accutane is not a problem, so please do not worry. Feel better soon.
It's best to consult your prescribing physician with this question. Most likely he or she will want to do a blood panel on you before you add anything else in. That way if anything does change down the line, you'll know what caused it. This is what I usually suggest when patients want to...
Some people are slow to respond to Accutane, and this is unfortunate. Usually these types of patients, though, do not have good responses to any medications, and thus, they just need to be on Accutane longer and a bit higher dosage. Having a worse initial breakout at the beginning is very...