ATROVENT Inhalation Aerosol has been used concomitantly with other drugs, including sympathomimetic bronchodilators, methylxanthines, and steroids, commonly used in the treatment of chronic obstructive pulmonary disease. With the exception of albuterol, there are no formal studies fully evaluating the interaction effects of ATROVENT Inhalation Aerosol and these drugs with respect to effectiveness.
Anticholinergic agents: Although ipratropium bromide is minimally absorbed into the systemic circulation, there is some potential for an additive interaction with concomitantly used anticholinergic medications. Caution is therefore advised in the co-administration of ATROVENT Inhalation Aerosol with other anticholinergic-containing drugs.
Acute overdosage by inhalation is unlikely since ipratropium bromide is not well absorbed systemically after aerosol or oral administration. The oral median lethal dose of ipratropium bromide ranged between 1001 and 2010 mg/kg in mice (approximately 30,000 and 60,000 times the maximum recommended human daily inhalation dose on a mg/m2 basis, respectively); between 1667 and 4000 mg/kg in rats (approximately 100,000 and 240,000 times the maximum recommended human daily inhalation dose, respectively, on a mg/m2 basis); and between 400 and 1300 mg/kg in dogs (approximately 80,000 and 260,000 times the maximum recommended human daily inhalation dose, respectively, on a mg/m2 basis).