Disclosed are novel compounds of the formula ##STR1##

wherein M¹ is CH or N and M² is C(R³) or N; R¹ is optionally substituted indolyl or an aza derivative thereof; R² is optionally substituted aryl or heteroaryl; and the remaining variables are as defined in the specification. Also disclosed are pharmaceutical compositions comprising the compounds of formula I. Also disclosed are methods of treating various diseases or conditions, such as, for example, allergy, allergy-induced airway responses, and congestion (e.g., nasal congestion) using the compounds of Formula I. Also disclosed are methods of treating various diseases or conditions, such as, for example, allergy, allergy-induced airway responses, and congestion (e.g., nasal congestion) using the compounds of formula I in combination with a H₁ receptor antagonist.