ATCvet Classification

Plain preparations

Plain/monovalent preparations are defined as preparations containing one active component (including stereoisomeric mixtures), and additional substances intended to

• increase the stability of the preparations (e.g. acetylsalicylic acid + ascorbic acid), or
• increase the duration of the effect (e.g. depot formulations), or
• increase the absorption of the active component (e.g. different solvents in dermatologicals).

Different salts of the active ingredient are usually given one and the same 5th level ATCvet code, but prodrugs and stereoisomers with differing pharmacological activity may be assigned separate 5th level codes.

Combined preparations

Preparations containing two or more active components are classified as combined products in accordance with the principles of the ATC system. The main therapeutic use decides which ATCvet code is to be used.

Combined products are classified according to two main principles:

1. Combined preparations containing two or more active components not belonging to the same therapeutic 4th level group are classified using 50-series codes.
    
   E.g.:
   QJ01AA06 Oxytetracycline (plain)
   QJ01AA56 Oxytetracycline, combinations
    
   Combined preparations with the same main active ingredient are usually given the same ATCvet code. Thus oxytetracycline + flunixin and oxytetracycline + neomycin are both assigned the code QJ01A A56.
    
2. Combined preparations containing two or more active ingredients belonging to the same therapeutic 4th level group are classified using the 5th level codes 20 or 30.
    
   E.g.:
   QJ01CA Penicillins with extended spectrum
   QJ01CA02 Pivampicillin
   QJ01CA08 Pivmecillinam
   QJ01CA20 Combinations
    
   For example, pivampicillin and pivmecillinam, and any other combinations including two or more active ingredients belonging to QJ01CA - Penicillins with extended spectrum, are given the ATCvet code QJ01CA20.

Combinations of substances used exclusively in veterinary medicine have earlier been given the 5th level code 99.

Separate ATCvet 3rd or 4th level codes have been assigned to certain important combinations, e.g. QJ51R - Combinations of antibacterials for intramammary use.

The main therapeutic use decides which ATCvet code is to be used. A preparation containing vitamins and iron used primarily as an iron preparation should be classified in QB03 - Antianemic preparations. Likewise, a product containing vitamins and antibiotics should be assigned to QJ - Antiinfectives for systemic use.

The sequence of classification codes of combined products should as far as possible agree with the order of classification of the single substances in question. In some ATCvet groups a ranking is needed to help in the classification of combination products (e.g. in QN02B and QJ51R). This ranking shows which substances take precedence over others when the classification is decided.