The Info List - Anatomical Therapeutic Chemical Classification System

The Anatomical Therapeutic
Chemical (ATC) Classification System
is used for the classification of active ingredients of drugs according to the organ or system on which they act and their therapeutic, pharmacological and chemical properties. It is controlled by the World Health Organization Collaborating Centre for Drug
Statistics Methodology (WHOCC), and was first published in 1976.[1] This pharmaceutical coding system divides drugs into different groups according to the organ or system on which they act or their therapeutic and chemical characteristics. Each bottom-level ATC code stands for a pharmaceutically used substance, or a combination of substances, in a single indication (or use). This means that one drug can have more than one code: acetylsalicylic acid (aspirin), for example, has A01AD05 (WHO) as a drug for local oral treatment, B01AC06 (WHO) as a platelet inhibitor, and N02BA01 (WHO) as an analgesic and antipyretic. On the other hand, several different brands share the same code if they have the same active substance and indications.


1 History 2 Classification

2.1 First level 2.2 Second level 2.3 Third level 2.4 Fourth level 2.5 Fifth level 2.6 ATCvet

3 Defined daily dose 4 Adaptations and updates 5 See also 6 References 7 External links

History[edit] The ATC system is based on the earlier Anatomical Classification System, which is intended as a tool for the pharmaceutical industry to classify pharmaceutical products (as opposed to their active ingredients).[2] This system, confusingly also called ATC, was initiated in 1971 by the European Pharmaceutical Market Research Association (EphMRA) and is being maintained by the EphMRA and the Pharmaceutical Business Intelligence and Research Group (PBIRG). Its codes are organised into four levels.[3] The WHO's system, having five levels, is an extension and modification of the EphMRA's. It was first published in 1976.[1] Classification[edit] In this system, drugs are classified into groups at five different levels:[4] First level[edit] The first level of the code indicates the anatomical main group and consists of one letter. There are 14 main groups:[5]

Code Contents

A Alimentary tract
Alimentary tract
and metabolism

B Blood
and blood forming organs

C Cardiovascular system

D Dermatologicals

G Genito-urinary system
Genito-urinary system
and sex hormones

H Systemic hormonal preparations, excluding sex hormones and insulins

J Antiinfectives for systemic use

L Antineoplastic
and immunomodulating agents

M Musculo-skeletal system

N Nervous system

P Antiparasitic
products, insecticides and repellents

R Respiratory system

S Sensory organs

V Various

Example: C Cardiovascular system Second level[edit] The second level of the code indicates the therapeutic subgroup and consists of two digits.[6] Example: C03 Diuretics Third level[edit] The third level of the code indicates the therapeutic/pharmacological subgroup and consists of one letter. Example: C03C High-ceiling diuretics Fourth level[edit] The fourth level of the code indicates the chemical/therapeutic/pharmacological subgroup and consists of one letter. Example: C03CA Sulfonamides Fifth level[edit] The fifth level of the code indicates the chemical substance and consists of two digits. Example: C03CA01 Furosemide ATCvet[edit] The Anatomical Therapeutic
Chemical Classification System
for veterinary medicinal products (ATCvet) is used to classify veterinary drugs. ATCvet codes can be created by placing the letter Q in front of the ATC code of most human medications. For example, furosemide for veterinary use has the code QC03CA01. Some codes are used exclusively for veterinary drugs, such as QI Immunologicals, QJ51 Antibacterials for intramammary use or QN05AX90 amperozide.[7] Defined daily dose[edit] Main article: Defined daily dose The ATC system also includes defined daily doses (DDDs) for many drugs. This is a measurement of drug consumption based on the usual daily dose for a given drug. According to the definition, "[t]he DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults."[8] Adaptations and updates[edit] National issues of the ATC classification, such as the German Anatomisch-therapeutisch-chemische Klassifikation mit Tagesdosen, may include additional codes and DDDs not present in the WHO version.[9] ATC follows guidelines[10] in creating new codes for newly approved drugs. In order to create a new ATC code, an application has to be sent to the WHO. New ATC codes are published twice annually.[11] A formal release of new ATC edition occurs once a year. See also[edit]

Classification of Pharmaco- Therapeutic
Referrals (CPR) ICD-10 International Classification of Diseases International Classification of Primary Care (ICPC-2) / ICPC-2 PLUS Medical classification Pharmaceutical care Pharmacotherapy RxNorm


^ a b "ATC/DDD Methodology: History". WHO Collaborating Centre for Drug
Statistics Methodology.  ^ "Comparison of the WHO ATC Classification & EphMRA/PBIRG Anatomical Classification" (PDF). EphMRA. Retrieved 7 January 2017.  ^ "EphMRA Anatomical Classification Guidelines 2016" (PDF). EphMRA. Retrieved 7 January 2017.  ^ "ATC: Structure and principles". WHO Collaborating Centre for Drug Statistics Methodology.  ^ "ATC/DDD Index". WHO Collaborating Centre for Drug
Statistics Methodology.  ^ the Anatomical Therapeutic
Chemical (ATC) classification system Structure ^ "ATCvet". WHO Collaborating Centre for Drug
Statistics Methodology. Retrieved 2015-02-15.  ^ "DDD: Definition and general considerations". WHO Collaborating Centre for Drug
Statistics Methodology.  ^ "ATC-Klassifikation mit DDD: Gesetzlicher Hintergrund" (in German). Deutsches Institut für Medizinische Dokumentation und Information.  ^ "Guidelines for ATC classification and DDD assignment". WHO Collaborating Centre for Drug
Statistics Methodology. 2014-12-16. Archived from the original on 2015-08-06.  ^ "New ATC". WHO Collaborating Centre for Drug
Statistics Methodology. 2015-04-29. 

External links[edit]

"WHOCC Homepage". WHO Collaborating Centre for Drug
Statistics Methodology.  "ATC: Introduction". Family Medicine
Research Centre, University of Sydney.  EphMRA Anatomical Classification (ATC and NFC)

v t e

Pharmacology: major drug groups

Gastrointestinal tract/ metabolism (A)

stomach acid

Antacids H2 antagonists Proton pump inhibitors

Antiemetics Laxatives Antidiarrhoeals/Antipropulsives Anti-obesity drugs Anti-diabetics Vitamins Dietary minerals

and blood forming organs (B)


Antiplatelets Anticoagulants Thrombolytics/fibrinolytics


Platelets Coagulants Antifibrinolytics

Cardiovascular system (C)

cardiac therapy/antianginals

Cardiac glycosides Antiarrhythmics Cardiac stimulants

Antihypertensives Diuretics Vasodilators Beta blockers Calcium channel blockers renin–angiotensin system

ACE inhibitors Angiotensin II receptor antagonists Renin inhibitors


Statins Fibrates Bile acid sequestrants

Skin (D)

Emollients Cicatrizants Antipruritics Antipsoriatics Medicated dressings

Genitourinary system (G)

Hormonal contraception Fertility agents SERMs Sex hormones

Endocrine system (H)

Hypothalamic–pituitary hormones Corticosteroids

Glucocorticoids Mineralocorticoids

Sex hormones Thyroid hormones/Antithyroid agents

Infections and infestations (J, P, QI)

Antimicrobials: Antibacterials (Antimycobacterials) Antifungals Antivirals Antiparasitics

Antiprotozoals Anthelmintics Ectoparasiticides

IVIG Vaccines

Malignant disease (L01–L02)

Anticancer agents

Antimetabolites Alkylating Spindle poisons Antineoplastic Topoisomerase inhibitors

Immune disease (L03–L04)


Immunostimulants Immunosuppressants

Muscles, bones, and joints (M)

Anabolic steroids Anti-inflammatories


Antirheumatics Corticosteroids Muscle
relaxants Bisphosphonates

Brain and nervous system (N)

Analgesics Anesthetics

General Local

Anorectics Anti-ADHD agents Antiaddictives Anticonvulsants Antidementia agents Antidepressants Antimigraine
agents Antiparkinson
agents Antipsychotics Anxiolytics Depressants Entactogens Entheogens Euphoriants Hallucinogens

Psychedelics Dissociatives Deliriants

Hypnotics/Sedatives Mood Stabilizers Neuroprotectives Nootropics Neurotoxins Orexigenics Serenics Stimulants Wakefulness-promoting agents

Respiratory system (R)

Decongestants Bronchodilators Cough medicines H1 antagonists

Sensory organs (S)

Ophthalmologicals Otologicals

Other ATC (V)

Antidotes Contrast media Radiopharmaceuticals Dressings Senotherapeutics

v t e

Medical classification

Topographical codes



SNOMED T axis MeSH A axis

Diagnostic codes



11 (not yet released; in development) 10 9

ICPC-2 DRC NANDA Read codes SNOMED D axis



IV 5


Procedural codes

HCPCS (CPT, Level 2) ICD

10 PCS 9-CM Volume 3 ICHI

NIC SNOMED P axis OPS-301 Read codes/OPCS-4 CCAM LOINC

Pharmaceutical codes


Outcomes codes


Pharmacy and pharmac