Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services if hiccups occur with trouble breathing, chest pressure or pain, facial drooping, weakness on one side, difficulty speaking, confusion, or a sudden severe headache.
These symptoms matter more than the hiccups themselves and may signal a medical emergency.
Seek same-day medical advice if hiccups prevent you from eating, drinking, or sleeping.
Repeated vomiting, signs of dehydration, or severe exhaustion also need prompt attention.
Signs of dehydration include a very dry mouth, dark urine, urinating much less than usual, or feeling faint.
Book a routine medical appointment if your hiccups last longer than 48 hours, keep returning, or are becoming more frequent.
You should also arrange an assessment if they began after starting a medicine or are accompanied by ongoing heartburn, coughing, unexplained weight loss, or difficulty swallowing.
Every sign above is quoted from the sofidex article on Hiccups. If you are not sure, err upward — it is always reasonable to be checked.