HCPCS Level II code S3722 denotes dose optimization by area under the curve (AUC) analysis for infusional 5-fluorouracil, a pharmacokinetic service used to tailor dosing of continuous 5-FU chemotherapy. This testing service is clinically important because AUC-guided dosing can reduce toxicity and help achieve therapeutic exposures for cytotoxic chemotherapy agents administered by infusion. Nationally, pharmacokinetic dose adjustments for 5-FU are relevant to oncology practices, hospital outpatient infusion departments, and clinical laboratories supporting chemotherapy monitoring.

Key payers considered in this summary include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise description of the service represented by S3722, the typical sites of service where it is performed, and the clinical rationale for AUC-based dosing. The publication includes benchmarks and policy-related context where available, outlines common billing considerations, and highlights how payers approach coverage and coding for pharmacokinetic dose optimization services. Data not available in the input is noted where applicable.