The paper examines the formulation of the antihistamine loratadin into hydrogels, the polymers under evaluation being Carbopol® 980 and Vivastar® P 5000. As other pharmaceutical auxiliary substances from the group of humectants are an indispensable component of hydrogels, the paper evaluates their influence (glycerol – GL, propylene glycol – PG, and sorbitol – SO) on the structural viscosity and pH of hydrogels as well as pharmaceutical availability of loratadin. On the basis of the results of the study it can be concluded that from the viewpoint of dermal administration of loratadin the hydrogels of the following composition are optimal: 0.5% Carbopol® 980 + 5% SO and 1.5 % Vivastar® P 5000 + 5 % PG.

        Key words: hydrogels – Carbopol® 980 – Vivastar® P 5000 – loratadin – humectants