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Dr. Phil, MD
Dr. Phil, MD, Medical Doctor
Category: Drug Testing
Satisfied Customers: 56575
Experience:  Medical Doctor Trained at a Top Academic Institution
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Would your answer be the same for a single use of cocaine in

Customer Question

Would your answer be the same for a single use of cocaine in the last 90 days?
Your previous answer is pasted below for reference.
Hair is relatively insensitive to rare use of marijuana. There is no specific number of uses that should be considered "safe", but there is much misunderstanding of the effectiveness of hair testing in the detection of occasional use of marijuana. Some other drugs are better detected, but marijuana typically needs use on a more regular basis over a 90 day period.
Here is a press release from Quest - one of the largest drug testing labs in the country. I bring your attention to this particular sentence; "Hair testing will not detect a single instance of drug use, but rather a pattern of repetitive use over a period of up to 90 days."
If you are subject to random hair tests you should of course not depend on this fact, since the amount needed to cause a positive will vary based on a number of factors including hair color.
HOWEVER, if you are having a drug test and are worried because you used once or twice, it is VERY likely that you would not fail based on this small exposure.
Submitted: 1 year ago.
Category: Drug Testing
Expert:  Dr. Phil, MD replied 1 year ago.

Thanks for this question


Definitely yes

The answer is the same for one use of cocaine over the past 90 days

let me know if you have other questions.

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Expert:  Dr. Phil, MD replied 1 year ago.

thanks for this question

please don't forget a positive rating. I appreciate it. :)

if you have more questions, just reply