It is nasty stuff and completely unnecessary.
Flea dip is essentially heavy duty flea shampoo but with the advantage of more of a residual effect. This was fine in the days before products like Frontline Plus and Advantage but now it is overkill and possibly even hazardous. It is actually kind of nasty stuff and there really is no good reason to take the chance that your pet will have a bad reaction to it. Just use regular flea shampoo.
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