I Was Treated For Diverticulitus And Sent Home With Flagyl,

I was treated for diverticulitus and sent home with Flagyl, Cipro and Zofran. The pharmacy filled it. I was told today from another pharmacy that there is a strong drug interaction between Cipro and Zofran. This is not the first time I have been treated with both at the same time, 3 different doctors and 3 different pharmacies filled them. Is this a new interaction just posted?