1) If you are just visiting USA for a couple of days then you have to bring clothing suitable for the existing weather. If it is during Winter then you will need warm clothes.
a) Get at least Medical Insurance either from India or if you are visiting someone, ask them to arrange Medical Insurance for you. Medical treatment is expensive. Before coming to USA go for full medical check up with your family doctor.
b) If you are under medication, bring enough medicine with you so that it will last as long as you are here. Indian doctor?rescription is not valid in USA.
2) If you are coming to USA with H1/H4 or L1 visa then the following things you should consider bringing with you are
a) Cotton clothes (pants, shirts) as these are cheaper in India. Ladies must bring Saris, Salwars from India only. Here these are expensive as these are imported from India. Alteration of pants/shirts is costly.
b) Cotton undergarments , the more you bring the better as cotton products are costly here.
c) Warm cloths , bring sweaters as pure wool cloths are expensive. Do not bring warm jackets from India, as jackets here are better than that available in India, except leather jackets.
d) One pressure cooker with some extra gaskets and safety valves. These are available in some states where Indian grocery is available, but again these will be costly.
e) A set of Thalis, glass and Katoris so that as soon as you land , you do not have to buy utensils.
f) 2-3 pair of business suits, if your office dress code is formal.
g) If you like leather jackets, then get it from India. It is expensive here.
h) Bring some medicine at least for Fever and upset stomach.
i) If you are using glasses , before coming to USA , get your vision checked thoroughly and if you need glasses get it from India.
j) Before coming to USA go for full Dental checkup as well as cleaning, it is much cheaper in India.
k) Before coming to USA , going for a complete medical check up with your family doctor is recommended.