Vaginal Capsules: A Viable Alternative for the Delivery of Lactobacillus spp.

<i>Lactobacillus</i> spp. and other beneficial bacteria are predominant in the vaginal microbiota and represent an opportunity to correct dysbiosis if administered intravaginally. Since no commercial formulations are available, developing magistral formulations is an option, provided that they ensure viability and therapeutic efficacy. To evaluate their stability and culturability, four magistral formulations containing 10⁹ microorganisms were tested: vaginal capsules, vaginal ointment, gelatinous ovules, and waxy ovules. Certified strains of <i>L. crispatus</i>, <i>L. johnsonii</i>, <i>L. gasseri</i>, <i>Limosilactobacillus reuteri</i>, and <i>Lacticaseibacillus rhamnosus</i>, as well as a combination of the five, were used. The formulations were tested for pharmaco-technical stability using average weight and disintegration tests, as well as evaluation organoleptic. In addition, microbial recovery was evaluated by counting Colony-Forming Units (CFUs). All forms, except the gelatinous ovules, allowed microbial recovery at concentrations from 10⁷ to 10⁹ CFUs, ensuring stability for 60 days. The recovery varied depending on the strains and dosage forms employed, with the most favorable outcomes for vaginal capsules. This highlights the need for standardized strains and excipients in magistral formulations. Further studies are needed to evaluate the viability of other strains of different excipients, vehicles, or different storage; however, capsules have demonstrated efficacy and are an excellent candidate for vaginal use formulations of <i>Lactobacillus</i> spp.