| Sulphonamides | Over-synthesis of p-aminobenzoic acid Chromosomal mutations in the dihydropteroate synthetase gene No recorded plasmid-mediated resistance
| Not recommended |
| Thiamphenicol | | Not recommended |
| Penicillins | Chromosomal mutations in the penA, penB, ponA, mtrR promoter and mtrR genes Chromosomal mutation in the penC (pilQ2) gene has been described in the laboratory but the mutation affects pilus formation and is thus of doubtful significance in terms of naturally acquired infection Altered expression of the pem gene Plasmid-mediated production of β-lactamase
| Recommended only in areas where data from regular on-going local surveillance programmes confirm that over 95% of clinical isolates are susceptible to penicillins |
| Tetracyclines | Chromosomal mutations in the rpsJ, penB, mtrR promoter and mtrR genes Chromosomal mutation in the penC (pilQ2) gene has been described in the laboratory but the mutation affects pilus formation and is thus of doubtful significance in terms of naturally acquired infection Altered expression of the tem gene Plasmid-mediated production of the TetM protein
| Not recommended |
| Spectinomycin | | |
| Aminoglycosides | | Generally not recommended as first-line agents, although kanamycin and gentamicin are still used as such in certain resource-poor countries May be used as a second or third-line agent
|
| Macrolides | Chromosomal mutations in the 23sRNA rrl, the mtrR/mtrC promoter, mtrR and mtrC genes Chromosomal expression of ermB, ermC and ermF methylase-encoding genes Role of the chromosomally encoded mef gene is of uncertain significance No recorded plasmid-mediated resistance
| Azithromycin is not recommended as a first-line agent due to the ease with which resistance may occur Azithromycin recommended as a second or third-line agent Other macrolides are not recommended
|
| Quinolones | | Recommended only in areas where data from regular on-going local surveillance programmes confirm that over 95% of clinical isolates are susceptible to quinolones |
| Cephalosporins | Chromosomal mosaic penA genes Chromosomal mutations in the penA, penB, ponA, mtrR promoter and mtrR genes No recorded plasmid-mediated resistance
| Recommended as first-line agents, either intramuscularly (ceftriaxone) or orally (eg, cefixime, cefpodoxime, ceftibuten depending on local availability) In areas where gonococcal strains are circulating with decreased susceptibility to oral cephalosporins, intramuscular ceftriaxone should be used at higher doses (500 mg–1 g)
|