DD keeps being sick when hungry

[madmother1]

My DD is 17. She keeps being sick when going hours without eating. I've tried telling her that she has to eat regularly.
She is on the pill and I seem to remember being sick myself years ago when on it.
Anyone else suffer this?

Does she often go hours without eating OP?

Also keep in mind that the pill may not be effective if she is vomiting regularly, she'd require extra contraception

Is this acid reflux? Does she take a mouthful of food then it gets stuck and comes back up?

Fortunately she uses condoms as well. So no chance of pregnancy.
She went out yesterday all day and ate at around 12noon then nothing until 7pm! She was at a football match.
She suffers badly if we go out on a family meal later than her normal dinner time. She goes past the point of hunger and can't eat a full meal sometimes.
I've started telling her to have toast before going out if this happens.