Around seven months ago (in July), I had a single unprotected sexual encounter with a male of unknown STD status without ejaculation. A couple of days later, I got severe pain in my throat. I started testing right away:

1. vaginal swab is taken at 11 days after: positive for Candida albicans  (Fluconazole prescribed for one month), and HPV 16 found (prescribed Isoprinosine for one month). I took both of those prescriptions during the month (till the middle of Aug)  and kept testing. 

So, I have some concerns about my testing results if it's reliable based on prescriptions I was taking during the time of testing. Nowadays (7 months later), I discovered swollen peripheral lymph nodes on my neck on the right side. Before my period this side of my jaw and neck hurts. I got some front teeth pain and vaginal pain also. It feels like a pulling pain inside my vagina. I also feel pain in my liver area lately. I got seborrheic dermatitis in my head that I had never had before. I don't know if it is all connected, but I didn't have those symptoms before. Please let me know if I need to perform any of those tests again to exclude false results and if the prescriptions I was taking could somehow affect the reliability of those tests. 

In reviewing your symptoms, I see nothing that suggests any STI, including HIV. Even the initial throat pain probably was not an STI; sore throat is a rare outcome of any STI. And of course when you're close enough to have sex, you're obviously at risk for any garden variety respiratory viral infection someone might have. Combining these facts with the multiple negative tests you have had, I am confident you have none of the infections for which you were tested with negative results.

HPV of one type or another is present in up to 50% of people (age 20-40) tested for it (e.g. along with Pap smears); HPV16 is one of the most common types; and 11 days probably is too soon after exposure for a positive result. That infection probably preceded the sexual exposure in July. In any case, HPV doesn't cause any of the symptoms you report. Candida albicans, the other test with a positive result, is normal in the vagina:  in increased numbers, it causes vulvovaginal candidiasis, with genital itching, irritation and/or discharge, but a positive culture in and of itself doesn't mean very much. Like HPV, it is not the cause of any of your symptoms. I am confident no infection from the July sexual encounter explains any of your several ongoing symptoms.

To your main question:  Could fluconazole or isoprinosine interfere with the reliability of the tests that were done? First, this may not matter:  even if you had any of the infections mentioned, none is a plausible cause of the symptoms you report. Second, I also am confident that neither fluconazole nor isoprinsosine had any effect on your test results.

Perhaps HIV is most on your mind, right? No medications or medical conditions of any kind cause any sort of interference with the reliability of the HIV antigen-antibody (AgAb, 4th generation) blood tests. At one time there was concern that conditions or drugs that interfere or interact with the immune system could prevent or delay antibody production, rendering antibody testing negative. That never was more than a theoretical consideration, especially for the more recently developed antibody tests (third generation), with few or no scientific reports of such interference. Equally or even more important, if antibody production were inhibited, then HIV replication would be higher than otherwise, with even higher levels of HIV antigen detectable in the blood. That's one of the beauties of the AgAb tests:  because they detect both HIV antigen and anti-HIV antibody, the tests are universally positive in all persons with HIV more than a few weeks in duration. Hence your negative tests are unequivocal proof you do not have HIV. And there isn't even a theoretical reason to suppose fluconazole has any such effect. Finally, there is no biological reason that these drugs would interfere with any of the other tests you had, nor clinical experience that documents any such interference.

Prior to your question, I was completely unaware of isoprinosine, also called inosine pranobex. In order to answer your question, I did a quick review of the available medical literature. I find that isoprinosine has in vitro (i.e. laboratory experimental) evidence of potentially enhancing cellular immunity, but there are few data on clinical effectiveness. A few studies have purported to show benefit against certain viral infections, including HPV. However, I judge the scientific quality of that research to be very low. I'm a bit surprised you were prescribed it on account of HPV. A single study suggests a possible modest effect on more rapid clearance of pre-cncerous cellular abnormalities caused by HPV infection of the cervix, but it is not a treatment recommended by any standard STI treatment guidelines (e.g. the US CDC, UK's BASHH, Europe's ECDC, or the equivalent agencies of Australia, Canada, or other countries of which I am aware). (You can google the abbreviations if you're unaware of these agencies.)

So my advice is to not worry further about the July sexual encounter, in confidence that it is not the cause of any symptoms you report nor any other significant health problem. And to keep working with your doctor about the causes and potential treatment(s) for your symptoms.

I hope this information is helpful. Let me know if anything isn't clear.

HHH, MD

But these issues are unrelated to the rest of your concerns. I have never heard of any of the tests you had having delayed positive results as long as 14 weeks, the time of your last tests. The results truly do rule out any possibility you have any of those infections. 

Yes, HPV can be acquired from a single exposure. However, as I said above, it takes several weeks for a new HPV infection to be detectable, and it is likely your HPV infection preceded the July event; 11 days is too soon. In any case, you should follow your doctor's advice about follow-up of your cervical HPV infection and cytology. The timing usually depends primarily on the initial cytologic findings. If the pap showed high grade intraepithelial lesions (HSIL), probably s/he will would recommend follow-up and perhaps treatment (e.g. colposcopy with biopsy and perhaps laser cautery) in a few weeks. If low grade (LSIL) or normal cytology, probably recheck in a year or so. But each case should be individualized. 

That concludes the two follow-up exchanges included with each question and so ends this thread. I hope the discusison has been helpful. Best wishes to you.