Will you pass a hair follicle test if you have used cocaine one time in the past 12 months?

12 months it should be out of your system

The above statement is correct, however one would need more information to better answer the question. First of all, drug metabolites are present in your hair forever, they do not just disappear. By law, drug testing labs are only permitted to go back 90 days when performing a hair test and only use the first 1.5 inches of hair. With that being said, we would need to know when the last time of usage was in relation to the upcoming test. If you used cocaine within the 90 day window before your test, then you will fail it, no questions asked. Even a VERY small amount of usage (a milligram) will cause you to fail as the test records the amount of drug metabolites in parts per million present in the inner cortex of hair and the cutoff threshold for cocaine is extreme low. For example, I know someone who failed the test after doing a key bump 2.5 months before the test. Just because your urine is clean DOES NOT mean that the drug metabolites have left your hair.

If you have not used in the last 90 days then I would suggest cutting your hair down to 1 inch to 1.5 inches in order to remove any evidence of use. If you HAVE used in the past 90 days and the test is within a month then you are going to fail miserably unless you find a way to remove the metabolites from your hair (which is possible if you search online) but DO NOT rely on the hair follicle shampoos advertised online and/or at head shops. Some of them may work when combined with other methods but the failure rate of these products alone is much higher than the success rate. My best advice would be to do some research online by going to member forums on sites like grasscity and marijuana dot com. Take an at-home urine test (buy one at your local pharmacy) and test yourself to see if your urine is clean of all substances. If it is then this generally means that the metabolites are no longer present in the new hair growth (still present in the older section of the same hair strand.) Good luck.