Thanks for writing to us.
The biological testing means they will test your urine, blood and hair samples for the presence of a controlled substance like oxycodone
If the hair sample is taken then there is no way to beat it.
For blood or urine sample, stop taking any drug right now, drink plenty of fluids and diluted apple cider vinegar to enhance the excretion of the drug.
I hope this information has been both informative and helpful for you.
Dr. Rakhi Tayal