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How Long Will Amoxicillin Remain In The System?
Question: How long will amoxicillin stay in your system? How many days since your last pill of amoxicillin Do you have to wait to make sure it won't interfere with syphilis blood test
Brief Answer:
TPHA is not affected by antibiotic course unlike VDRL test
Detailed Answer:
Hello. Thank you for writing to us
I am dr.kakkar (dermatologist and venereologist). I have gone through your query and I have noted your concern.
A full course of oral penicillin taken anytime after syphilis infection can influence VDRL test which is a non specific test for syphilis. The antibiotic might delay seroconversion or the VDRL titres might fall after antibiotic treatment. Therefore it would not be reliable to have a wash off period after oral antibiotics for a VDRL test. Rather it would be better to go for a specific test like TPHA if one expects such a scenario. A specific test for syphilis e.g TPHA test stays positive throughout life irrespective of treatment.
Regards
TPHA is not affected by antibiotic course unlike VDRL test
Detailed Answer:
Hello. Thank you for writing to us
I am dr.kakkar (dermatologist and venereologist). I have gone through your query and I have noted your concern.
A full course of oral penicillin taken anytime after syphilis infection can influence VDRL test which is a non specific test for syphilis. The antibiotic might delay seroconversion or the VDRL titres might fall after antibiotic treatment. Therefore it would not be reliable to have a wash off period after oral antibiotics for a VDRL test. Rather it would be better to go for a specific test like TPHA if one expects such a scenario. A specific test for syphilis e.g TPHA test stays positive throughout life irrespective of treatment.
Regards
Note: Consult a Sexual Diseases Specialist online for further follow up- Click here.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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