One of the most important decisions you must make when agreeing to take certain meds, is the ingredients that accompanies the active ingredient, as in, all my meds are sugar free, lactose free and certain others, aspirin is enteric,.
Side effects are common in most meds, and it would never surprise me that the patient is unaware of both the sugars or ingredients can and do increase glucose levels and symptoms.
Some anti biotics are just, minimum dosage, minimum anti biotic, maximum sugars! Same with cold and flu remedies.
You just have to know your meds.