I did under .5 grams of cocaine and took a drug test 90 hrs later. i'm not a frequent user. i weigh 165 pounds and am 5'10. will i pass my urinalysis?

Not likely: a half gram is a large amount of cocaine at one time, and would mean to me that you are setting yourself up for a serious problem, or you may have one already, no matter how infrequently you use. The average line of cocaine is about 100 mg so this would be 5 lines. Cocaine sticks around for up to 5 days, particularly in large amounts. Talk to a drug counselor or your physician about your use.