Table of Contents

Urine Drug Screen

Primer

The Urine Drug Screen (UDS) has several limitations, including only testing for a limited for a number of drugs, plus false positives/negatives are common. There can be a lack of temporal correlation with the UDS result and the clinical presentation. Urine drug screens at one hospital are also not always the same at another site.

Indications

Should Urine Drug screens Ordered Routinely in the ER?

Urine drug screens at the emergency department level does not improve the routine management of psychiatric patients.[1][2] However, despite its limitations, the urine drug screen is useful for psychiatrists when there are challenges in determining a whether a patient has a primary psychotic disorder versus a substance-induced psychotic disorder.[3]

False Readings

Approach

Opioids

Tricyclics

Resources

References

1) Tenenbein, M. (2009). Do you really need that emergency drug screen?. Clinical Toxicology, 47(4), 286-291.
2) Kroll, D. S., Smallwood, J., & Chang, G. (2013). Drug screens for psychiatric patients in the emergency department: evaluation and recommendations. Psychosomatics, 54(1), 60-66.
3) Latt, N., Jurd, S., Tennant, C., Lewis, J., Macken, L., Joseph, A., ... & Long, L. (2011). Alcohol and substance use by patients with psychosis presenting to an emergency department: changing patterns. Australasian psychiatry, 19(4), 354-359.
4) Saitman, A., Park, H. D., & Fitzgerald, R. L. (2014). False-positive interferences of common urine drug screen immunoassays: a review. Journal of analytical toxicology, 38(7), 387-396.
5) Geraci, M. J., Peele, J., McCoy, S. L., & Elias, B. (2010). Phencyclidine false positive induced by lamotrigine (Lamictal®) on a rapid urine toxicology screen. International journal of emergency medicine, 3(4), 327-331.