Famvir/Valtrex

[Nikkir]

I have Shingles and the doctor had prescribed Valtrex 1 gm to be taken 3 times a day. So far so good. It's been a week. I went in to see him again today and he said it's healing and drying up. I told him I was almost out of the valtrex he had prescribed and also told him I was in between insurances so this is all out of pocket right now. They were out of Valtrex samples so he nicely gave me a weeks worth of Famvir(famciclover) 500 mg saving me a bit of cash.

What I didn't understand was that he said they were both the same, and that taking 500 mg of Famvir was the same as taking Valtrex 1 gm and I am to take it 3 times a day just like the Valtrex.

Does this sound right? Does anyone have any experience with this?

Thanks for all your help!

Nikkir

[MikeGinny]

Nikkir,

Famcyclovir (FAMVIR) is about twice as potent as valacyclovir (VALTREX), which means that roughly half the amount will do the same job. Mind you, they're both equally EFFECTIVE, it's just that it takes less famcyclovir to do the same job. I don't have time to look it up right now, but I think this is because famcyclovir is better absorbed from the GI tract than valacyclovir.

As for them being the "same," that's basically true. They are slightly different, but they both attack the same viral enzyme and they both basically work in the same way. There are some minor differences that are of interest to molecular virologists and pharmacologists, but there is no clinical significance to these difference that we know of.

Your doctor's advice is sound.

------------------
-Mike
Certified Mad Scientist

"90% of people are
caused by accident."

[Nikkir]

Thanks alot Mike! I wanted to be sure because it seemed like I was having good results with the Valtrex with no side affects, so I was a little afraid to switch.

You had said on the other thread, that having Shingles serves to "re-immunize" you against chicken pox. How can this be if people get it again and sometimes again and again? I've heard everything and I certainly know it's an individual thing, but could you please explain that a bit more. Unfortunately there is no shot for this sort of thing. Thanks!

Nikkir