QUOTE(mcsexy @ Mar 26 2008, 10:29 PM)

I am taking diet pills ,is it okay to bring pills in the US or any types of medicine like birth pills too..just curious

It may depend on three things: are the meds controlled substances like pain meds in the US (illegal unless prescribed by a US doctor); what quantity you are bringing with you (a large supply may be a problem as you could be seen as intending to sell them); and random luck as to whether you get your bags searched or not. I'd check it out before bringing them. If nothing else, bring them in the original bottles to show they were obtained legally in your country.
Many drugs in foreign countries are not controlled and may be purchased "over the counter"" at a store, but they may be controlled in the US and available only from a doctor.
"Diet pills" have a bad connotation in the USA from the old speed craze days when they were often abused.