So Hankster, who suggested that it might be from biking, can very well be right. I did a web search for "biking sex" and sure enough, biking is a proven, well documented cause of ED and it is supposed though not researched enough that women are equally affected.

Damn it!

I started biking just slightly earlier than Topamax. So now I do not know what is the culprit.

I will have a two week break from biking when I go to Europe and we will see if I get better.

Biking is such a great cardiovascular activity, and commuting by bike weaves exercise into my day absolutely painlessly, it would be such a shame if I have to stop because of this damn thing!