whats always worked for my pets - from your local food coop or health food store - dr. bronners magic soaps
eucalyptus oil soap.
put a small amount, maybe 1/20 - 1/10 of bottle, of eucalyptus oil soap in bottle, fill with water. spray. can be used on all types of critters to get rid of the littler critters and it is biodegradable soap and it works as a mosquito spray also. magical stuff.
yea, i use it as shampoo also.