What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveOrder

LOINC Code 78436-3: Primidone and PHENobarbital trough panel

Name: LOINC Code 78436-3: Primidone and PHENobarbital trough panel
Creator: HealthAssure Clinical Team
Published: 2026-05-21T09:00:00.203Z

78436-3 is a LOINC code used to identify Primidone and PHENobarbital trough panel in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Primidone & PHENobarbital trough panel. It is commonly used with the system or sample type Ser/Plas.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Primidone & PHENobarbital trough panel. It is commonly used with the system or sample type Ser/Plas.

When is it used?

Used in lab systems, EHRs, and clinical data exchange.
May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
Status: ACTIVE
Order vs observation: Order
Panel type: Panel

What it does not mean

The code identifies the observation or test, not the actual result.

Key facts

Primidone and PHENobarbital trough panel - Serum or Plasma
Primidone & PHENobarbital trough panel
Primidone and phenobarbital trough levels are measured for therapeutic anticonvulsant monitoring.
Barbiturate; c417; DRUG/TOXICOLOGY; Drugs; Luminal; Mysoline; Nirvonal; Pan; PANEL.DRUG & TOXICOLOGY; Panl; PHBR; Phenobarb; Pl; Plasma; Plsm; Pnl; Point in time; Primdne + PHENobar Trgh Pnl; Primidone+Phenobarb; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Primidone and PHENobarbital trough panelPrimidone and PHENobarbital trough panel - Serum or PlasmaPrimdne + PHENobar Trgh Pnl SerPlPrimidone & PHENobarbital trough panelPANEL.DRUG/TOXPrimidone and PHENobarbital Trough Panel, Blood-

Frequently asked questions

Code details

Code78436-3

SystemLOINC

Display namePrimidone and PHENobarbital trough panel

DescriptionPrimidone & PHENobarbital trough panel

Short namePrimdne + PHENobar Trgh Pnl SerPl

ComponentPrimidone & PHENobarbital trough panel

Property-

TimingPt

System (specimen)Ser/Plas

ScaleQn

ClassPANEL.DRUG/TOX

StatusACTIVE

Order/ObservationOrder

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.54

Last changed2.54

Consumer names

Primidone and PHENobarbital Trough Panel, Blood

Part names

Primidone & PHENobarbital trough panel-PtSer/PlasQnPrimidone and PHENobarbital trough panelPoint in time (spot)Serum or Plasma

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.