Hi, If you have a recent history of unprotected sexual exposure, this could be an STI, a sexually transmitted infection.
The common sexually transmitted infections which would produce a discharge like yours are: Chlamydia, Neisseria gonorrhoeae, syphilis and Trichomonas vaginalis. You should consult a doctor, you will need blood and/or urine tests to rule out an infection. Please look up this link: http://en.wikipedia.org/wiki/Sexually_transmitted_disease
The supplement that you mention would not cause this.
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