Pediatric Coding Alert

Question: We perform urine tests on our patients who have ADD (attention deficit disorder)/ADHD (attention deficit hyperactivity disorder) to make sure they are taking their prescribed Ritalin. What ICD-10 codes should we use to map with the 80305 code?

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Answer: CPT^® code 80305 (Drug test(s), presumptive, any number of drug classes, any number of devices or procedures; capable of being read by direct optical observation only (eg, utilizing immunoassay [eg, dipsticks, cups, cards, or cartridges]), includes sample validation when performed, per date of service) is a simple urinalysis drug test that can be read by direct observation. CPT^® classifies the test as a presumptive drug class procedure, meaning that the test provides information about whether the patient is, or is not, using a drug.

The test does not verify whether the patient has therapeutic levels of Ritalin in his or her system. For that, you will need a therapeutic drug assay, which CPT^® tells you “are performed to monitor clinical response to a known, prescribed medication.” That means using 80360 (Methylphenidate), which is a quantitative test typically conducted by an outside laboratory.

The distinction between the tests is important, as it will inform your ICD-10 code choice. As 80360 monitors therapeutic drug levels, you would use Z51.81 (Encounter for therapeutic drug level monitoring), along with a code for long-term (current) drug therapy, which in this case would be Z79.899 (Other long term (current) drug therapy). But for 80305, you would only use Z79.899.

You would use Z51.81 and/or Z79.899 as primary diagnosis codes in these encounters, along with the appropriate code from F90.- (Attention-deficit hyperactivity disorders) for the various conditions related to ADHD or F98.8 (Other specified behavioral and emotional disorders with onset usually occurring in childhood and adolescence) for ADD.

Beware this dx! One code you should not use in this encounter, unless your pediatrician’s notes indicate otherwise, is F15.90 (Other stimulant use, unspecified, uncomplicated). While it does indicate that the patient is using a stimulant such as Ritalin, use of the F code in this instance indicates that the patient is misusing the drug and not taking it for therapeutic purposes.