Process for preparing a solid preparation of a penicillin derivative

Abstract

A process for freeze-drying a penicillin derivative of the formula: ##STR1## wherein R is a hydrogen atom or a hydroxyl group, by evaporating a frozen aqueous solution of the penicillin derivative (I) under vacuum from the frozen state to dryness, which is characterized by maintaining the temperature of the frozen solution within a range from the eutectic point of the solution determined by the electric resistance method to -8.degree. C. when the penicillin derivative of the formula (I) wherein R is a hydrogen atom is to be freeze-dried, or -10.degree. C. when the penicillin derivative of the formula (I) wherein R is a hydroxyl group is to be freeze-dried during the primary drying period of the drying process.

Dependencies are inferred from the claim text.