Medication!!

Has anyone had reactions to Medication with certain food? Or with certain mixes of Medication causing sickness, upset tummies and tummy cramps? I know that there is always side effects with medication but I've never know medication react with food! I'm not sure which it is or if it's not any of these and I'm just suffering with some sort of unlucky repeating bug that just keeps coming back! But I'll wake up and literally stand up and I need to get to the loo quick and then it starts!! Back and forth to the loo being sick or the other! And it just seems to be intermittent some times a day or a few days then I'm fine then next day maybe it starts again or I'll have a few days fine then boom it's back! So if anyone has any answers, if they can't eat certain foods with their meds or know of any bugs like this? I would love to know please!!