it’s a common anti-opioid and it shouldn’t be taken by people still taking opioids. Because if its proximity to that usage, drug testing before prescribing is the rational, reasonable, logical thing for them to do first.
However, your consent should not be a buried-in-long-boiler plate paperwork you sign.
They should additionally tell you in person, face to face, asking for your explicit consent to be drug tested.
I agree with you.