Why ask? Unless your "gas" reflects an atypical heart attack symptom, food poisoning, an obstruction, or ileus (& by taking an otc simethicone pill you are delaying procurement of appropriate medical care), I can't think of too many other circumstances in which the otc gas reduction pill in question would be contraindicated after a bbq. Is there further concern or more to your question you have not shared?
Yes. Yes the over-the-counter gas reducers are fine.