Help!! I think my piggy is dying :(

Question
My husband noticed a couple days ago that our guinea pig, Sugar was acting strange.  Ever since we have had our two piggys, Sugar & Spice, Sugar has scratched herself til she gets little scabs.. sometimes they would bleed.  In less than a weeks time she has scratched SO much that is raw and bleeding.  She has been crying and hasn't drank hardly any water for 2 days.  After much research tonight, I think Sugar has Mites (mange) and she has started having seizures.  I feel absolutly horrible we didn't figure this out sooner.  We can't afford to take her to a vet.. what should we do?  I feel so helpless that I can't help her.  Is there anything over the counter that we can get to help her or can we purchase the Ivermectin from a pet supply or feed store??  Any advice would be greatly appreciated.

Mona

Answer
You can purchase the medication from a horse supply store. The thing is you still need to talk to a vet and ask them how much you should dilute the ivermectin and which one would be best as the horse Ivermectin is concentrated. I'm sure the vet won't charge to ask questions on how much you should use since you can buy Ivermectin over the counter.