That's not what my doctor led me to believe. Dr Lerner's writes in his protocol that an initial worsening of symptoms is to be expected before improvement.
There are many types of side effects from taking medications. Not all are herx reactions, and not all are normal.
I agree that there is often a temporary worsening of symptoms, particularly with Valcyte. I had a very bad stretch with Valcyte that didn't start until 4 months into treatment. Mine appeared to be an IRIS-type reaction. However, an IRIS reaction doesn't happen immediately upon taking a medication, as yours appears to have done.
This sounds like a die-off reaction.
That's not possible with valacyclovir and valgancyclovir. The symptoms you are having are not caused exclusively by "die-off". The body and the medicines we put in it are an extremely complex system. There are any number of reasons one might have allergic-type reactions. One is that you are having an allergic reaction to the medication, which should be checked with your prescribing doctor. Another is that you are having an allergic reaction to something entirely unrelated to the medication. There are plenty of other reasons as well.
Why do you think this happens?
Impossible to say. It could be any of very many things. This is something you should discuss with your physician.
I don't think it's simply adjusting to the medication.
Why? That would be the most likely explanation.
I haven't noticed too many side effects from the valaciclovir. I'm not terribly familiar with antivirals but the allergy type symptoms for me are a sign of herxing. I'm also taking olmesartan so I will continue to get some herx response.
Valacyclovir is a relatively "easy" medication. Most patients don't have side effects from it, although I'm sure some do. Valgancyclovir is another story. Many people have side effects of some kind from it.
Allergy-type symptoms are commonly (but not exclusively) the result of some kind of immune response, but without testing you're not likely to know exactly what kind of immune response or what is causing it. "Herxing" is a much overused, and usually incorrectly used , explanation for immune reactions. It is relatively rare and can only occur in very specific situations, and taking antivirals is not one of them.
From Dr Lerner's writings, I understand the main risks are kidney and liver function problems. He has said valaciclovir is safe to use, although he exercises more caution with valganciclovir. But so long as liver and kidney values don't indicate any problems, I believe they are safe. I've read some information about antivirals affecting white blood cell count and mitochondria production, but I haven't come across this in Dr Lerner's writings yet (I still have a lot of reading to do).
One of the most serious side effects of valgancyclovir is neutropenia. Dr Lerner is very well aware of this and tests for it and liver function every 4-6 weeks. I agree that
if you are being tested often enough for potential side effects, valgancyclovir is
relatively safe. I wouldn't have allowed my teenager to take it if I didn't believe that. That doesn't make it a medication without risk, just one where the risks can be managed with very careful management and supervision.
Since you seem to be a fan of Dr Lerner, I will share some insights from having been a patient of his. He does
not consider Valcyte (valgancyclovir) a "safe" medication. He is very well aware of the risks and is extremely strict about monitoring for them. He will immediately take a patient off Valcyte if side effects develop. He will only prescribe 4-6 weeks at a time to make sure that patients come in to get regular blood tests. No tests, no Valcyte. He believes Valcyte is a valuable medication in ME/CFS treatment and that it can be used safely with
careful management and knowledgeable supervision. He does not take it lightly, or prescribe it indiscriminately.
Dr Lerner does not believe, at all, that the difficult period some people have with Valcyte is a herx reaction. He would chide you if you told him it was.
He acknowledges the situation, but to my knowledge has never tried to explain it. He is an infectious disease doctor, not an immunologist.