A method for lysing a fixed biological sample to obtain a lysate that is suitable for direct use in a subsequent nucleic acid analysis method. The method includes contacting the fixed biological sample with an aqueous lysis composition to obtain a lysis mixture, and heating the lysis mixture at ≧85° C. to obtain the lysate. Inhibitors of the subsequent nucleic acid analysis method are depleted by contacting the fixed biological sample in the first step with at least one compound which prevents or reduces the inhibition of the subsequent nucleic acid analysis method, and/or binding inhibitors to a solid support having an anionic surface. The method is rapid, efficient, does not require the use of chaotropic salts and does not require a prior purification of nucleic acids prior to performing the subsequent analysis method. A portion of the obtained lysate can be used directly, for example, in an amplification reaction.