Research, Society and Development, v. 10, n. 11, e368101119348, 2021 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v10i11.19348 1 The effect of splitting on the quality and in vitro release of metformin hydrochloride from extended-release (XR) tablets O efeito da divisão na qualidade e na liberação in vitro de cloridrato de metformina de comprimidos de liberação prolongada (XR) El efecto de la división sobre la calidad y la liberación in vitro del clorhidrato de metformina de las tabletas de liberación prolongada (XR) Received: 08/12/2021 | Reviewed: 08/16/2021 | Accept: 09/02/2021 | Published: 09/04/2021 Luiz Gustavo da Fonseca Santos ORCID: https://orcid.org/0000-0001-9298-6468 Universidade Federal de São João del-Rei, Brazil E-mail: luizgustavo_fs@hotmail.com Adriana Inés Segall ORCID: https://orcid.org/0000-0001-9758-7896 Universidad de Buenos Aires, Argentina E-mail: asegall@ffyb.uba.ar Yong Ki Han ORCID: https://orcid.org/0000-0001-5371-630X Universidad de Buenos Aires, Argentina E-mail: calidad815@gmail.com Maria Patricia Kizelman ORCID: https://orcid.org/0000-0001-8128-1104 Universidad de Buenos Aires, Argentina E-mail: pkizelman@ffyb.uba.ar Maíra Peres Ferreira ORCID: https://orcid.org/0000-0002-0385-6416 University of São Paulo, Brazil E-mail: maira@fcfrp.usp.br Amanda Cristina Funari Silva ORCID: https://orcid.org/0000-0003-4613-0700 University of São Paulo, Brazil E-mail: amandafunari@usp.br Frederico Severino Martins ORCID: https://orcid.org/0000-0001-5555-8771 University of São Paulo, Brazil E-mail: fredseverinomartins@gmail.com Whocely Victor de Castro ORCID: https://orcid.org/0000-0002-8354-1843 Universidade Federal de São João del-Rei, Brazil E-mail: whocely@ufsj.edu.br Osvaldo de Freitas ORCID: https://orcid.org/0000-0001-7055-2028 University of São Paulo, Brazil E-mail: ofreitas@fcfrp.usp.br Renê Oliveira do Couto ORCID: https://orcid.org/0000-0002-3748-3427 Universidade Federal de São João del-Rei, Brazil E-mail: rocouto@ufsj.edu.br Abstract Metformin hydrochloride (MetCl) is used worldwide in the treatment of type-2 diabetes mellitus. Although extended- release (XR) tablets containing 500 mg, 850 mg, and 1000 mg of MetCl are marketed, it is not uncommon to split the tablet when the dosage form of the required strength is not available commercially. The aim of work was to evaluate the effects of splitting on the in vitro performance of XR tablets containing MetCl. We performed quality control assays and comparative dissolution profile studies among several medicines containing 500 mg and 1000 mg of MetCl, marketed in Brazil and Argentina. Tablets containing 1000 mg of MetCl were halved (test samples) and compared with whole tablets of products containing 500 mg of MetCl (reference samples). The halved tablets were more fragile and presented lower uniformity of mass and dosage unit as compared to the whole ones. However, it was evidenced by the F2 bootstrapping parameter that splitting MetCl XR tablets did not significantly impact the in vitro drug release profiles