The invention provides a preparation containing an antibiotic, with the exclusion of &bgr-lactam antibiotics, and silver in the form selected from nano- or microparticles and silver compound, for use in the treatment of infections caused by bacteria resistant against the antibiotic. It further provides use of this preparation for the treatment of surfaces and/or material against resistant bacteria. The invention further includes an antibiotic preparation containing a mixture of an antibiotic, with the exclusion of &bgr-lactam antibiotics, and silver nano- or microparticles, without a chemical bond between the antibiotic and silver. The present preparations are useful in particular in human or veterinary medicine, medical tools and materials, or in cosmetics to eliminate bacterial infections caused by classical antibiotic-resistant bacteria. &dot
