Glad you asked.

Our present antivirals, acyclovir, valtrex and famvir are very safe and have a long track record as such. Some people, including doctors who are not up to date confuse them with some older antivirals such as foscarnet that do have some potential for serious side effects connected with the liver or kidneys.

Acyclovir and valtrex are considered so safe that they are routinely given to pregnant women in the third trimester to suppress genital OBs at delivery.

These antivirals are specifically targetted to a unique chemical reaction that is necessary for viral transcription, the process whereby the DNA chain in the infected cell breaks and creates a new viral particle. The woman who invented acyclovir won a Nobel Prize for her work.

In general, I recommend that people start with generic acyclovir as it is so much less expensive as compared to Valtrex and Famvir, which are still covered by patents.

I hope this helps.

Disclaimer: I am not a medical doctor, but I used to live next door to one, and I've, consulted over the years with well-known experts and researchers in the field.