The cuteness of your sweet pup can only be marred by one thing: his ability to get dirty. Whether he's been rolling in the mud or mucking through your garbage, he's going to need a bath at some point. Using the right shampoo keeps his sensitive skin and coat healthy.
Your little fluffball has young skin which is still sensitive. Strong chemicals, dyes and perfumes can make him itchy and miserable, but puppy shampoos are generally mild. They are designed to get him clean and then wash away completely, without leaving residue. Most are tearless as well. Getting your puppy to remain still anywhere is a challenge, but inside the bathtub, it's likely impossible. That means a stray bubble or two might slip into his eyes as he squirms and wiggles, so a tearless shampoo is a must if you ever want to get him back in the tub.
If you can't find a puppy shampoo or don't want to buy different shampoos for your adult dog and puppy, you can use some dog shampoos safely with your little guy. Adult shampoos that are designed for sensitive skin should work on your puppy's skin as well. Check the ingredient list to make sure you recognize most of the ingredients -- any artificial fragrances or colors can turn your puppy into a scratching maniac. Natural ingredients such as honey, vitamin E, aloe vera, lavender, chamomile and eucalyptus should be fine for your pup. Check with your vet to make sure the adult dog shampoo is appropriate for your puppy's needs.
Short-haired puppies probably won't need a conditioner, but if he has long hair, a conditioner can help keep his coat free of painful mats and tangles. Rub it over the surface of his fur without scrubbing, then rinse it away completely. A conditioner designed for puppies is best, since it's likely to be tearless, but a gentle adult dog conditioner can work in a pinch.
It's heartbreaking to think of your puppy dealing with annoying fleas and other insects such as ticks. If your pup is having a flea problem, talk to your vet before using a flea shampoo or any product that includes an insecticide. Most of these are too harsh for your puppy and contain powerful chemicals. Your vet might have other solutions that are safer for your little pooch.