@marieaw
Good morning! I have waited the 2 hours but some people think 2-4 is better. Waiting does not make me happy but the reason for waiting is logical because you are trying to rid your body of the bad with the antibiotics and then at the same time taking a probiotic to provide good bacteria. Perhaps the following is helpful:

To maximize effectiveness:
Do not take probiotics at the exact same time as antibiotics; allow 2–4 hours between doses to prevent the antibiotic from killing the probiotic organisms. Continue probiotics for 1–2 weeks after finishing antibiotics, or longer if recommended by your healthcare provider.

Although not on the antibiotics as of today, I still take the Jarro daily and my body loves the extra help with good bacteria. You may want to run this by your provider but I think the answer will still be the same.
Best wishes!