This thesis delves into the crucial role of antimicrobial preservatives in external pharmaceutical formulations, with a specific focus on their efficacy in topical gels. Through adherence to European Pharmacopoeia guidelines and referencing the Hungarian national formulary, Formulae Normales VIII, various preservatives were rigorously evaluated. Findings reveal that benzoic and sorbic acid salts exhibit notable antimicrobial activity, suggesting their viability over traditional options like methyl paraben. Importantly, this study underscores the significance of selecting appropriate preservatives regardless of the gelling agent, aiming to enhance both safety and efficacy while addressing concerns regarding preservative toxicity and ensuring microbial stability throughout product shelf life.