510(k) Predicate Finder
Find potential predicate devices for your 510(k) submission. Enter a K-number to find all clearances with the same product code, a three-letter product code to browse clearances directly, or search by device name.
Nephelometric Inhibition Immunoassay, Diphenylhydantoin
Clinical Toxicology
A nephelometric inhibition immunoassay for diphenylhydantoin is a laboratory diagnostic test that measures diphenylhydantoin (phenytoin) levels using light-scattering immunoassay technology, used for therapeutic drug monitoring in patients with epilepsy. The device is FDA Class 2, representing moderate risk and requiring 510(k) premarket clearance. It bears product code LFO and is regulated under 21 CFR 862.3350 in the Clinical Toxicology specialty. This device is eligible for third-party review.
510(k) Clearances
1 matchesWhat is a Predicate Device?
A predicate device is a legally marketed device that a new 510(k) applicant uses to demonstrate substantial equivalence. The FDA's 510(k) pathway requires manufacturers to show that their device has the same intended use and similar technological characteristics as one or more predicate devices already cleared for commercial distribution.
Finding the right predicate is a critical step in 510(k) strategy. Manufacturers typically search for cleared devices with the same FDA product code, which groups devices by their intended use and regulatory classification. This tool helps you identify potential predicates by browsing all clearances within a product code.
Note that predicate devices must be legally marketed — they cannot be devices that were cleared but never commercialized, or devices subject to a mandatory recall. The determination of substantial equivalence considers intended use, technological characteristics, and performance data.