There is really no way of knowing. I doubt it unless it was really hot. The only way you'll know for sure is to keep using it and see if you notice a difference in how it effects you.
Does anyone know how this turned out? I can't believe I just did this again! I just noticed that I left my second bottle out this week. Aargh, the first one I just tossed because I was close to the 10 days anyways, but this new one is only two days old. I can't believe I did that! I don't know if it makes a difference, but I'm taking the sublingual Rx drops? It was only left out for about 7 hours. I was just going to order an injection kit and switch to injections, so I didn't want to waste a whole new container of hcg to use for only a few more days.