can i get an STD while on Keflex?

i was at the beginning of a 7-day treatment of Keflex (500mg) when i had unprotected sex with a lady. does this afford me any extra protection from STD's ? i know AIDS and herpes are still a worry, but what about the usual suspects like ghonorea (Gonorrhea) or syphilys? its been almost 5 weeks with no symptoms and im going to get an HIV test, but should i get the full battery of tests? just wondering.. thanks!
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[H. Hunter Handsfield, M.D.]

Complete protection against gonorrhea and syphilis; probably substantial but incomplete protection against chlamydia.  As you say, no protection against HIV, HPV, or herpes.

The chance of getting chlamydia from a single sexual encounter is low, and for the others (HSV, HIV) also low.  I suggest you don't get tested for anything, unless/until you develop symptoms.

HHH, MD

[nickyoo]

thanks in advance...
  Just a follow-up...still no usual sypmptoms, no burning or sores..there is some itching under the head of my penis and at the base.  the base i think is form shaving for a vasectomy 7 weeks ago, the head i think may be from using rubbing alcohol to clean myself after the encounter. could it be something else? even though i was somewhat protected with the keflex, could i still have passed it on to my wife? can any std's be passed on through breast milk? my wife said she is starting to feel like her periods are about to start again cause she has the familiar discomfort "down there". but she is still breastfeeding. she shouldnt start yet should she? im a bit worried about this if she is feeling funny and no period comes. im getting tested friday to end any specualtion, but even if im negative, could i have transmitted while on the anti-biotic?
thanks
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