Cephalosporins are wide range of antibiotics and they are effective against a wide range of bacteria. They kill bacteria and work in a similar way like penicillins. There are three generations of cephalosporins.
1st generation: They are highly effective against gram positive bacteria but rarely against gram negative, for e.g cephadrine and cephalexin.
2nd generation: They target few types of gram positive and gram negative bacteria and are less efficient against gram positive as compared to the first generation cephalosporins. For example cefprozil.
3rd generation: They are highly effective against gram negative bacteria and may work well for bacteria that are resistant to the first two generation. Example: Rocephin or cefixime.
STDs or sexually transmitted diseases like gonorrhea, syphilis chlamydia are caused by gram negative bacteria like Neisseria gonorrhoeae, Treponema pallidum or Streptococcus agalactiae etc.
