The present invention provides pharmaceutical compositions comprising azelastine, or a pharmaceutically acceptable salt or ester thereof including azelastine hydrochloride, and optionally one or more additional active agents. Preferred such compositions further comprise one or more pharmaceutically acceptable carriers or excipients that reduce the amount of post-nasal drip, and/or that minimize or mask the unpleasant bitter taste associated with post-nasal drip, of the compositions into the oral cavity, upon intranasal or ocular administration of the compositions. Especially effective excipients used in the compositions of the present invention are hypromellose as a viscosity modifier and sucralose as a taste-masking agent. The invention also generally relates to pharmaceutical compositions comprising one or more active pharmaceutical ingredients, such as azelastine or pharmaceutically acceptable salts or esters thereof including azelastine hydrochloride, particularly wherein the compositions are provided in unit dosage form. In certain embodiments, the invention provides such unit dosage pharmaceutical compositions comprising azelastine hydrochloride formulated for use as nasal sprays and/or ocular solutions or drops. The invention also provides methods of treating or preventing certain disorders, or symptomatic relief therefrom, by administering the compositions of the invention to a patient, e.g., for the symptomatic relief of a variety of allergic and non-allergic conditions, particularly conjunctivitis, sinusitis, rhinitis and rhinosinusitis. The compositions and methods of the present invention provide significant value in terms of patient acceptability, convenience, and compliance.