False negative

Noncompliance

Diversion

Repeat test using chromatography; specify the drug of interest

Before repeating the test take a detailed history of the patient’s medication use for the preceding 7 d

Ask patient if they’ve given the drug to others

If diversion is strongly suspected, assess for addiction to opioids, cocaine, etc; switch, taper, and discontinue the opioid, and refer for addiction treatment

False positive

Patient acquired drugs from other sources

Ask patient if they accessed opioids from other doctors or acquaintances

Assess for opioid misuse or addiction, and treat accordingly

False positive

Patient is an occasional user

Patient is addicted to the illicit drug

Assess for abuse or addiction

Refer for addiction treatment as appropriate

Consider tapering and discontinuing opioids if patient is currently addicted to other drugs (eg, cocaine); consider transferring to methadone or buprenorphine treatment

Patient is a social user

Patient uses it for pain

Patient is addicted to cannabis

Patient has concurrent psychiatric condition

Ask about cannabis use

If patient is a regular user (4 or more joints a week), advise abstinence or treatment if there is concurrent clinical depression, psychosis, or impairment in functioning, or if the patient is an adolescent

Patient added water to sample

Repeat UDS

Consider supervised collection or temperature testing

Take a detailed history of the patient’s medication use for the preceding 7 d

Review and revise the treatment agreement

Delay in handling sample (urine cools within minutes)

Patient added water to sample

Repeat UDS

Consider supervised collection or temperature testing

Take a detailed history of the patient’s medication use for the preceding 7 d

Review and revise the treatment agreement