Loracarbef is an orally administered member of a new synthetic class of beta-lactam antibiotics, the carbacephems, which is characterised by enhanced chemical stability. At low concentrations (< 2 mg/L) in vitro, it inhibits Streptococcus pneumoniae, S. pyogenes, beta-haemolytic streptococci groups B, C and G. Proteus mirabilis and Moraxella catarrhalis, including beta-lactamase-producing strains. At therapeutic plasma concentrations it is also active in vitro against most strains of Staphylococcus aureus, S. saprophyticus, Escherichia coli and beta-lactamase-positive and -negative strains of Haemophilus influenzae. Like other beta-lactams, loracarbef is inactive against methicillin-resistant strains of S. aureus. When administered at dosages of 200 to 400 mg twice daily, the clinical and bacteriological efficacy of loracarbef is comparable with that of amoxicillin and amoxicillin/clavulanic acid in patients with upper or lower respiratory tract infections, and comparable with that of cefaclor in treating infections of the lower respiratory tract, skin and skin structures and urinary tract. Loracarbef and phenoxymethylpenicillin (penicillin V) were equally effective in treating streptococcal pharyngitis and tonsillitis. Loracarbef is generally well tolerated by all age groups and causes less diarrhoea than amoxicillin/clavulanic acid. It is administered twice daily. It offers a suitable alternative to other orally administered antibiotics for the treatment of mild to moderate infections caused by susceptible organisms.