Virtually every fourth shop in India sells food. There is ample variety for both, vegetarians and non-vegetarians and the price range can match to anyone’s pocket. You can get a dish from $.35 (Rs.21) upto $10 (Rs. 640).
There is no doubt that Indian food is a treat to the taste-buds but can be harsh on your digestive system.
Take precaution if you eat at road-side stalls or at low-end restaurants. Request the server to get your silverware rinsed in boiling water even if you have to pay extra. Milk and milk products, spices and water are known to upset stomach. Look at this recent report http://indiatoday.intoday.in/story/delhi-street-food-test-restaurants-momos-contamination/1/440901.html.
Use bottled water only and that too from reputed shops. With poor outdoor air-quality in Delhi, especially from April to August, breathing-masks are advisable.
Some medicines you should carry to India are Tylenol/Advil, Alka Seltzer, Immodium, Robitussin/NyQuil with you. Medication that you can get over the counter at the Indian pharmacy/chemists shop: Indian Crosin (fever), Combiflam (ibuprofen), Norflox (diarrhea), Volini (spray for muscle spasms), Coldarin (cold and cough), Benadryl (cough).
It is also highly advisable to keep the items like hand sanitizer lotion, toilet rolls, and paper soap handy with you.