A metered-dose inhaler includes at least one vessel (50) and an actuator for receiving the at least one vessel. The at least one vessel (50) includes a first reservoir (31) containing a first formulation and a second reservoir (32) containing a second formulation. The metered-dose inhaler is actuable when the at least one vessel (50) is received by the actuator. The metered-dose inhaler is configured to simultaneously deliver a first metered dose of the first formulation and a second metered dose of the second formulation upon actuation.
