Your pet’s skin is different to your own. The pH balance is different and is also thinner than human skin, so use of human shampoo on your dog is not recommended. You should always use a shampoo specifically formulated for your pet’s skin. The TOTAL CARE range of dog shampoo is designed for adult dogs and puppies, and includes shampoos to treat fleas or skin irritations.
You should not need to shampoo your dog more than once a fortnight. This lets the natural oils in your dog's coat and skin do their work. You should not wash your dog for at least 48 hours after a spot-on or line flea treatment.