Which is better and where do i get Ivermectin and how to apply. i had some revolution ive been using but i dont think its doing its job plus i may have given my squirrel to much. he's better now i guess just not his old self because of the parasites .not sure what kind of parasites thinking its mange like last time. sleeps alot hum drum not a hundred percent. its been three weeks since dosage three drops. eating fine maybe just getting old (5). not intrested in outside much. was thinkink of going to vet tommorow getting more revolution. the revolution i used had been opened for about three months but was in a pill container . any thoughts .