Inhaled antiinfectives are classified in ATC group J - Antiinfectives for systemic use.
R07 - Other Respiratory System Products
R07A - Other Respiratory System Products
This group comprises lung surfactants and respiratory stimulants. Caffeine is classified in N06B - Psychostimulants, agents used for ADHD and nootropics. See also comments under R07AB - Respiratory stimulants.