lice and mites

Question
I had a guinea pig for 3 weeks now, I got it from adopt a guinea pig, but the first thing I noticed a day after I got him, he was scratching so when I checked it, there are little wounds in it and also at the bottom I see light brown things attached to the hair.  I bought a "Spot On" which it says it protects from mites and lice.  But still he is scratching, one week later, I tried the insecticidal shampoo. It's two days now since I shampooed him.  I noticed he is scratching the back of his ear, then I checked the bottom there are no lice that attached in the hair, but probably there are still coz sometimes he is still scratching, what will I do? Should I shampoo him again?

Answer
Hi Mona

The small wounds would indicate a mite problem rather than lice.

The shampoo is good at protecting against mites but once the condition is present, you need medecine to remove them. You will take to take your pig to the vet for a course of ivermectin which normally comes in 3 doses, one week apart.

Andy