I take metformin. The script stresses that it should be taken with breakfast. I don't consider single banana a breakfast.
I normally eat a small bowl of cereal as breakfast.
You need to take medication with food where there is a risk that the medicine will irritate your stomach or cause ulcers. If you can't face food, a glass of milk will do.
I can't remember what medication she took but my mum had one to be taken with food first thing in the morning. She couldn't eat breakfast but dr told her a mug of milk coffee and a couple of digestive biscuits were enough.