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80186 Assay of phenytoin free

Pathology & Lab

Also known as: phenytoin free level, free Dilantin level

Laboratory quantitative drug assay for phenytoin free serum fraction for therapeutic drug monitoring in seizure management.

In Plain Language

free phenytoin blood test; active seizure medication level

Clinical Context

Measures unbound phenytoin; particularly valuable in patients with altered protein binding or renal/hepatic impairment.

RVU Information

CPT 80186 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.

Billing & Documentation

Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.

How This Code Compares

This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.

Specialties

PathologyNeurologyClinical Pharmacology

Frequently Asked Questions

What is CPT code 80186?

CPT 80186 (Assay of phenytoin free) is a Pathology & Lab code. Laboratory quantitative drug assay for phenytoin free serum fraction for therapeutic drug monitoring in seizure management.

Who uses CPT code 80186?

CPT 80186 is used by Pathology, Neurology, Clinical Pharmacology. Measures unbound phenytoin; particularly valuable in patients with altered protein binding or renal/hepatic impairment.

When is CPT 80186 used?

Measures unbound phenytoin; particularly valuable in patients with altered protein binding or renal/hepatic impairment.

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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.