Why are nebulized short-acting beta-agonists (SABAs) dosed higher than inhalers?

Nebulized short-acting beta-agonists (SABAs) are indeed dosed higher than those delivered via metered-dose inhalers due to the larger particle size associated with nebulization. When SABAs are nebulized, the aerosol particles tend to be larger, which can affect how the medication is distributed within the respiratory tract.

Larger particles are less likely to reach the deeper parts of the lungs, where they can be most effective in treating obstructive airway conditions. As a result, to ensure that a sufficient amount of the medication reaches the target areas and achieves the desired therapeutic effect, higher doses are needed when delivering the medication via a nebulizer compared to an inhaler.

This approach balances the delivery mechanism's inefficiencies with the need for adequate therapeutic concentrations in the lungs. The corrected dosing compensates for the potential loss of efficacy due to particle size and distribution, thereby ensuring effective management of symptoms associated with conditions like asthma or COPD.