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.

This group comprises agents used for various indications, e.g. hypotension. Respiratory stimulants are classified in R07AB.
Dihydroergotamine, which is used in the treatment of migraine as well as hypotension, is classified in N02CA - Ergot alkaloids.
Combinations with peripheral vasodilators, see C04 - Peripheral vasodilators.

This group comprises sympathomimetics used in the treatment of hypotension. Centhaquine for the treatment of hypovolemic shock is classified here.
Etilefrine in combination with dihydroergotamine is classified in this group.
Oral products of ephedrine are classified in R03CA.