atc code r06 atc code r06 atc code r06 antihistamines for systemic use is a therapeutic subgroup of the anatomical therapeutic chemical classification system, a system of alphanumeric codes developed by the world health organization (who) for the classification of drugs and other medical products. subgroup r06 is part of the anatomical group r respiratory system. atc codes r respiratory system r01 nasal preparations r02 throat preparations r03 drugs for obstructive airway diseases r05 cough and cold preparations r06 antihistamines for systemic use r07 other respiratory system products a b c d g h qi j l m n p r s v codes for veterinary use (atcvet codes) can be created by placing the letter q in front of the human atc code: for example, qr06. national issues of the atc classification may include additional codes not present in this list, which follows the who version. r06a antihistamines for systemic use r06aa aminoalkyl ethers r06aa01 bromazine r06aa02 diphenhydramine r06aa04 clemastine r06aa06 chlorphenoxamine r06aa07 diphenylpyraline r06aa08 carbinoxamine r06aa09 doxylamine r06aa10 trimethobenzamide r06aa11 dimenhydrinate r06aa52 diphenhydramine, combinations r06aa54 clemastine, combinations r06aa56 chlorphenoxamine, combinations r06aa57 diphenylpyraline, combinations r06aa59 doxylamine, combinations r06aa61 dimenhydrinate, combinations r06ab substituted alkylamines r06ab01 brompheniramine r06ab02 dexchlorpheniramine r06ab03 dimetindene r06ab04 chlorphenamine r06ab05 pheniramine r06ab06 dexbrompheniramine r06ab07 talastine r06ab51 brompheniramine, combinations r06ab52 dexchlorpheniramine, combinations r06ab54 chlorphenamine, combinations r06ab56 dexbrompheniramine, combinations r06ac substituted ethylene diamines r06ac01 mepyramine r06ac02 histapyrrodine r06ac03 chloropyramine r06ac04 tripelennamine r06ac05 methapyrilene r06ac06 thonzylamine r06ac52 histapyrrodine, combinations r06ac53 chloropyramine, combinations r06ad phenothiazine derivatives r06ad01 alimemazine r06ad02 promethazine r06ad03 thiethylperazine r06ad04 methdilazine r06ad05 hydroxyethylpromethazine r06ad06 thiazinam r06ad07 mequitazine r06ad08 oxomemazine r06ad09 isothipendyl r06ad52 promethazine, combinations r06ad55 hydroxyethylpromethazine, combinations r06ae piperazine derivatives r06ae01 buclizine r06ae03 cyclizine r06ae04 chlorcyclizine r06ae05 meclozine r06ae06 oxatomide r06ae07 cetirizine r06ae09 levocetirizine r06ae51 buclizine, combinations r06ae53 cyclizine, combinations r06ae55 meclozine, combinations r06ak combinations of antihistamines empty group r06ax other antihistamines for systemic use r06ax01 bamipine r06ax02 cyproheptadine r06ax03 thenalidine r06ax04 phenindamine r06ax05 antazoline r06ax07 triprolidine r06ax08 pyrrobutamine r06ax09 azatadine r06ax11 astemizole r06ax12 terfenadine r06ax13 loratadine r06ax15 mebhydrolin r06ax16 deptropine r06ax17 ketotifen r06ax18 acrivastine r06ax19 azelastine r06ax21 tritoqualine r06ax22 ebastine r06ax23 pimethixene r06ax24 epinastine r06ax25 mizolastine r06ax26 fexofenadine r06ax27 desloratadine r06ax28 rupatadine r06ax29 bilastine r06ax31 quifenadine r06ax32 sequifenadine r06ax53 thenalidine, combinations r06ax58 pyrrobutamine, combinations