Background Antimicrobial use in long-term care facilities (LTCF) is an important public health issue, especially regarding its potential role in antimicrobial resistance. Up to two thirds of long-stay LTCF residents receive antimicrobial therapy each year. However, little is known specifically about antimicrobial use in short-stay LTCF residents receiving post-acute care. Methods The authors conducted a retrospective chart review of a random sample of residents admitted for post-acute care in seven LTCFs in Georgia from September 1, 1999 to August 31, 2000 to determine the rates and characteristics of antimicrobial prescribing in this population. Results Of 221 post-acute care residents, 105 (48%) received 152 courses of antimicrobial therapy during their post-acute stay. At least one antimicrobial was prescribed on 796 of 5220 resident-days (15%). Antimicrobial therapy was split evenly between hospital-initiated antimicrobial therapy (n = 53, 50%) and antimicrobial therapy initiated in the LTCF during post-acute care (n = 52, 50%). Levofloxacin was the most commonly prescribed antimicrobial. Where documentation on the suspected infection was present, the most common infections were urinary tract infections (UTIs) and pneumonias. For residents with post-acute care-initiated therapy, documentation regarding the presumed source of infection was absent for 44% of antimicrobial prescriptions. Most antimicrobial courses initiated for presumed infections in post-acute care were by telephone orders (66%). Conclusions Utilization of antimicrobial therapy in LTCF residents in post-acute care is relatively high and may be greater than for long-stay LTCF residents. For hospital-initiated therapy, improved communication between hospital and LTCF staff may improve documentation and antimicrobial therapy in LTC. For antimicrobial therapy initiated by telephone orders in post-acute care, improving documentation of suspected source of infection is needed. Antimicrobial use in long-term care facilities (LTCF) is an important public health issue, especially regarding its potential role in antimicrobial resistance. Up to two thirds of long-stay LTCF residents receive antimicrobial therapy each year. However, little is known specifically about antimicrobial use in short-stay LTCF residents receiving post-acute care. The authors conducted a retrospective chart review of a random sample of residents admitted for post-acute care in seven LTCFs in Georgia from September 1, 1999 to August 31, 2000 to determine the rates and characteristics of antimicrobial prescribing in this population. Of 221 post-acute care residents, 105 (48%) received 152 courses of antimicrobial therapy during their post-acute stay. At least one antimicrobial was prescribed on 796 of 5220 resident-days (15%). Antimicrobial therapy was split evenly between hospital-initiated antimicrobial therapy (n = 53, 50%) and antimicrobial therapy initiated in the LTCF during post-acute care (n = 52, 50%). Levofloxacin was the most commonly prescribed antimicrobial. Where documentation on the suspected infection was present, the most common infections were urinary tract infections (UTIs) and pneumonias. For residents with post-acute care-initiated therapy, documentation regarding the presumed source of infection was absent for 44% of antimicrobial prescriptions. Most antimicrobial courses initiated for presumed infections in post-acute care were by telephone orders (66%). Utilization of antimicrobial therapy in LTCF residents in post-acute care is relatively high and may be greater than for long-stay LTCF residents. For hospital-initiated therapy, improved communication between hospital and LTCF staff may improve documentation and antimicrobial therapy in LTC. For antimicrobial therapy initiated by telephone orders in post-acute care, improving documentation of suspected source of infection is needed.