Medical Pharmacology Chapter 35  Antibacterial Drugs

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Sexually Transmitted Diseases:  Drug Treatment
  • Syphilis

    •  Serologic Testing

    • Early (primary, secondary, or latent {< one-year})

      •  Primary treatment:

        •  Penicillin G benzathine --(single dose)

      •  Alternative treatment:

        •  Doxycycline (Vibramycin, Doryx) -- multiple dose, 14 day duration

    • Late (> one-year duration, cardiovascular, gumma, late-latent)

      •  Primary treatment:

        •  Penicillin G benzathine --(multiple dosing, 3 weeks)

      •  Alternative treatment:

        •  Doxycycline (Vibramycin, Doryx) -- (multiple dosing, 4 weeks)

    • Neurosyphilis

      •  Primary treatment:

        •  Penicillin G --(multiple dosing, 10-14 days)

      •  Alternative treatment:

        •  Penicillin G procaine-- (IM daily + probenecid (Benemid): 10-14 days)

      •  Penicillin-allergic patients-should be the sensitized

    • Congenital

      •  Primary treatment:

        •  Penicillin G or

        •  Penicillin G procaine

      •  Newborn -- positive serological syphilis test without stigmata of syphilis:

        •  Passive transfer of maternal antibodies

        •  Prenatal infection

        •  Treat seroreactive infants immediately rather than waiting to determine if antibody titer falls (3-6 months).

    • Syphilis in pregnancy:

      • Penicillin G

      • No need to re-treat in subsequent pregnancy unless clinical or serological evidence of active/persistent infection

      • Pregnant women with penicillin allergy:

        1.  Hospitalization

        2.  Desensitization

    • Syphilis and AIDS

      • standard penicillin treatments recommended (with normal CSF)

        • For some patients: higher doses, longer treatment required

      •  In some cases, high-dose IV treatment may not cure symptomatic neurosyphilis in HIV patients.


     Reference: "Drugs for Sexually Transmitted Infections", The Medical Letter, vol. 41 (issue 1063), September, 24, 1999, Published by the Medical Letter, Inc, New Rochelle, N.Y.


    • Penicillin Review

      • Bacteriocidal for sensitive strains

      • Inhibits cell wall synthesis

      • Primarily affects gram-positive microbes

      • Relatively non-toxic

      • For both penicillins and cephalosporins, bacteriocidal properties require that bacterial cells are actively growing and synthesizing cell walls.

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