Preparation of a tetracycline topical formulations
The invention relates to a topical suspension formulation that includes a tetracycline, a liq. medium and a polymeric gelling agent. The tetracycline may be in the form of its salts, hydrates, or polymorphs and is in a suspended form within the formulation. The liq. medium is selected such that it does not completely dissolve or minimally dissolves the tetracycline. The gelling agent is a polymeric hydrocarbon gelling agent. Preferably, the tetracycline has a particle size of ≤20 μ. A formulation contained minocycline free base (cryst.) 1, mineral oil 30, and Versagel-M750 69%.