A person eats street food, stale food, ice-cream, watery fruits, or something that didn’t suit them. Within a few hours, things start going downhill. They feel intense nausea and keep vomiting again and again, even after taking small sips of water. There’s a burning pain in the stomach, as if the inside is raw or on fire. The throat and chest burn with acid rising up, leaving a bitter or sour taste. They feel very thirsty, but can only drink small sips at a time—large amounts make the vomiting worse. There is restlessness and anxiety, they can’t lie peacefully, keep changing position, and feel extremely weak and exhausted. Sometimes there’s vomiting of bile, greenish fluid, or even blood-stained vomit in severe cases. The person feels icy cold, drained, and may even feel faint. Eating or drinking even a little causes severe stomach pain. Oddly, despite all this, they may crave milk, coffee, or sour things, though these often aggravate the condition. Arsenicum album is a classic remedy to think of.