Valtrex affect IgG

Does taking Valtrex affect IgG numbers?

Yes. Terri Warren recommends stopping for a “couple months” to get a more accurate result.

Thanks.. but it shouldn't lower the number right? I can understand it affecting the ability to build more antibodies but it should not lower your number if you are already positive... or am I wrong?

and thanks for getting back to me :)

I’m not an expert, but here’s the scenario I’ve read about it affecting the number. Let’s say you have a primary outbreak and you’re diagnosed visually or by swab and the doctor puts you on antivirals right away. If you then want to get a blood test, it can make it appear that you’re testing negative because it slows down the virus and as a result the antibodies you’re just starting to build. Warren’s book says if you go on antivirals right away and do a blood test shortly after but test negative, you should really come off the meds for a couple of months and retest. Hope that makes sense!

I’ve never read anything about lowering the number after you’ve tested positive. Maybe someday I’ll do another STD panel and see if my index values change since I’m on antivirals.

Here's my situation.. I've already spoken to Terri and I am going ahead with the WB to confirm HSV2. But I am now 13 weeks out. In November at about 8 weeks my igg was .97. then at 11 weeks it was 1.38, at 12 weeks it was 1.62, at this point I started the valtrex (which was Wednesday of last week), then Monday I had another igg test at 13 weeks and it came back at 1.33. I don't know if the valtrex would cause it to drop or if this is considered normal variation. Maybe I'm just slow at building antibodies but I am 13 weeks out and have only been on the meds for 1 week.

I thought I read once that some slight variation was natural. I’m glad you’re going to do the western blot for some answers once and for all!

Me too.. and after speaking to Terri, it seems that 12 weeks is actually ok to do the western blot... we shall see

Yes as well as may cause macrocytosis, which I have developed twice since being on chronic suppressive therapy with 1 gm of valcyclovir per day. Typically, the doctor will recommend you come off the medication for a few months until the numbers normalize.

@teekay. Did I‎t cause your numbers to be really low?

Not excessively low because I have regular blood draws to monitor my red blood cell. My most recent blood draw showed an increased MCV and low red blood cell count, so I am on a three to six month break from the antiviral. So far, so good. It has been 3 years since diagnosis, so here is hoping the antibodies are pretty good and I can come off the medication. :-)

@teeKay what was you IgG at? Was that affected by the Valtrex at all?

I don't believe so.