The vet clinic I worked at most recently, we used this shampoo stuff called "Skunk Off" I think it what it was called... We had a shepherd mix come in once that had just gotten skunked and I worked on her for a couple hours atleast, maybe more....

First she got a bath with skunk off... and I follow the directions on the bottle.. afterwards still very strong skunk smell.. so finally I had to do another bath on her, I soaked her down with this shampoo head to toe used a whole bottle on a 45lb dog.... and then put her in a run in Iso (because she had the whole hospital smelling).. and let that shampoo soak on her for over an hour... then threw her back in the tub and hosed her off... I think by the time she was dry she was tollerable... but if she got just alittle wet for several months afterwards she smelled like a skunk again...