No single third-generation cephalosporin treats all infectious disease scenarios.Ĭefotaxime and ceftizoxime (discontinued) offer the best gram-positive coverage out of all the third-generation agents ceftazidime and cefoperazone (discontinued) are unique in that they provide antipseudomonal coverage.Ĭeftriaxone has a long half-life which allows for once daily dosing and may be used for the treatment of gonorrhea, pelvic inflammatory disease, and epididymo-orchitis. Third generation cephalosporins followed the second-generation cephalosporins. Second-generation cephalosporins are more active against gram-negative bacteria, with less activity against gram-positive bacteria. There are also differences with regards to how frequently the different first-generation cephalosporins need to be dosed. They have little activity against gram-negative bacteria.Ĭephalexin and cefadroxil can be given by mouth, whereas cefazolin can only be given by injection (IV/IM). Their optimum activity is against gram-positive bacteria such as staphylococci and streptococci. First generation cephalosporinsįirst generation cephalosporins refer to the first group of cephalosporins discovered. Within each generation, there are differences in terms of administration (such as oral or intravenous administration), absorption, excretion, and how long the activity of the cephalosporin lasts in the body. There are five “generations” of cephalosporins, with each generation differing slightly in their antibacterial spectrum (ie, how effective they are at killing certain types of bacteria). What are the differences between cephalosporins? What are cephalosporins used for?Ĭephalosporins may be used to treat infections caused by susceptible bacteria, such as: Note that this classification system is not used consistently from country to country. Most cephalosporins start with cef, ceph, or kef. There are five generations of cephalosporins. Each time the structure changed, a new 'generation' of cephalosporins were made. They are called broad-spectrum antibiotics because they are effective against a wide range of bacteria.Īfter the first cephalosporin was discovered in 1945, scientists improved the structure of cephalosporins to make them more effective against a wider range of bacteria. They bind to and block the activity of enzymes responsible for making peptidoglycan, an important component of the bacterial cell wall. Cephalosporins are bactericidal (kill bacteria) and work in a similar way to penicillins. Cephalosporins are a large group of antibiotics derived from the mold Acremonium (previously called Cephalosporium).

Gram negative antibiotics chart