Low dose, only insignificant systemic and metabolic exposure.

Selective HI-antagonist used in local treatment of allergic rhinitis. Nasal spray, each dose containing 50 µg levocabastine. Recommended dose gives plasma concentrations in the range 2-9 µg/mL. Excreted in unchanged form (70%) and as glucuronide.

Uneventful use reported in 3 patients with acute porphyria.