| | | C - Cardiovascular System |  | This group comprises substances used for the treatment of cardiovascular conditions.Drugs used for the treatment of hypertension are classified in C02 - Antihypertensives, C03 - Diuretics, C07 - Beta blocking agents, C08 - Calcium channel blockers, and C09 - Agents acting on the renin-angiotensin system. For the classification of combination products of antihypertensives from different ATC groups, the following ranking should be used, from higher to lower precedence: C09, C07, C08, and C03.
 
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 |  | | C09 - Agents Acting on The Renin-Angiotensin System |  |  |  | The DDDs are based on the treatment of mild-moderate hypertension.See comments to C02L concerning the principles for assignment of DDDs for combined preparations.
 
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 |  | | C09A - Ace Inhibitors, plain |  | All plain ACE inhibitors are classified in this group. No separate ATC codes are assigned for the active metabolites of the ACE inhibitors (e.g. enalaprilat, quinaprilat).Combinations with diuretics, see C09BA - ACE inhibitors and diuretics.
 Combinations with calcium channel blockers, see C09BB - ACE inhibitors and calcium channel blockers.
 Combinations with beta blocking agents, see C09BX - ACE inhibitors, other combinations.
 
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 |  | | C09AA - Ace Inhibitors, plain |  |  | 
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