Go to a doctor now if: Signs of dehydration (no wet nappies, no tears, very dry mouth, drowsiness) because the mouth is too sore to drink, a fever lasting beyond 3 days, a very unwell or floppy child, a stiff neck, or a baby under 3 months with fever - see a doctor.
Food-first comfort
Comfort and keep fluids going despite the mouth soreness: cool, soft, bland foods like curd/yoghurt, mashed banana, cool khichdi, custard, kheer or soft rice; cool (not iced) water, milk, coconut water and diluted juice offered little and often; avoid salty, spicy, citrus or crunchy foods that sting the sores; cool foods and drinks numb the mouth a little. Hydration is the priority.
What to nourish
Curd, banana, soft rice, dal, kheer, cool milk, coconut water - soft and bland while the mouth heals.
Never
Never give aspirin to a child with a viral illness. Don't force solid or spicy/salty food onto painful sores. Don't burst the blisters. Keep the child home from daycare/school while feverish or blistering to avoid spreading it, and no honey under 1 year.
Care at home
Hand, foot and mouth is a common, self-limiting viral illness that passes in about a week. The whole job at home is keeping the child comfortable and drinking - dehydration from a sore mouth is the main thing to watch.
Related guides
When to see a doctor. Children are not small adults. This guide offers food-first comfort for a parent to consider; it gives no medicines, doses or supplements for children. A paediatrician decides on treatment. When in doubt, go.