Can an employee refuse to allow a search of their personal pocketbook if it contains personal detailed medical information?

Question Details:

I was clocked out and leaving the workplace when a "loss prevention" employee demanded to look in my pocketbook. I refused because I was receiving treatment for a medical condition of a personal nature. He then told me that I had no choice and threatened to "arrest" me. (He is not a police officer.) I was prepared to be fired to maintain my privacy, but I was then accused of shoplifting and told that refusing the search was evidence of "suspicious behavior". Important Notice