SYPHILIS

Q: I have had syphilis before and it was treated with 100mg doxycycline 3 times daily for 2 weeks. treatment was started after a rash appeared.
That was 3 years ago.
Now i have a sore in the same area as before so i know it is the same thing again.No rash yet.
I started taking 100 mg of doxy 2 times daily.
it has been a week and the sore is still there , but shrinking.
Is the doxy working? How long should it take until the doxy , if working, should cause the sore to dissapate?

A: Penicillin is still the best medication for treatment of syphilis. I imagine you might have a penicillin allergy, which is why doxy was chosen? Doxycycline is used for syphilis. If you are taking the medication as prescribed which sounds like it, then it should be working (unless you are on other medications simultaneously, like seizure medications that decrease the effectiveness of doxy). It works by preventing the growth and spread of bacteria, not by killing the bacteria that is already there. So it can take a few days to kick in. I cannot tell you how long it will take for the sore to go away. Exercise caution, that the sore is still contagious. Just make sure that your infection is being followed by a physician because if improperly treated, there are serious consequences. Best of luck.