Lyophilised prepn. obtained by freeze drying a reversibly thermo-gelling water based composition is claimed. The gel contains an effective dose of a drug (D); 0.2-2.1 (w/v)% methyl cellulose (substitution deg. 26-33% OMe), 1.2-2.3 (w/v)% citric acid, and 0.5-13 (w/v)% polyethylene glycol.
