I need your help with puppy

Good Day Everyone,

I'm new to the site (love the site) and new to having a beautiful puppy named Versace. He is 5 months and we got him at 16 weeks. Born on Oct 20, 2008 and we adopted him on Feb 8, 2009. He is a full breed Shih Tzu and just the love of our lives. He has two human brothers ages 18 an 12 and a Daddy that just spoil him rotten.

He is doing really really good potty training but that took a lot of work. We have to carry him out due to the steps being too high for him to go up but he has within the last week start telling us he has to go out and we also keep an watchful eye on him also. We have used a crate from day one and never had one accident in the crate. He goes all night long without waking up. He also loves his crate. We try to keep him out with us as much as we can which is pretty much all day since I'm a stay at home Mom. The only time he goes in the crate is if I can't watch him or have to go out. Most of the time if I can I take him since he loves to ride in the car and lays right down in the back seat on him blanket.

Here's the big problem. When we brought him home he was on Eagle pack puppy dry food and Merrick puppy plate wet food mixed. He was never a big eater to begin with. We would have to really work to get him to eat. I have also stopped the Eagle pack dry since we found out it had wheat in it and he was scratching a lot and moved to the Merrick Puppy Plate dry food that you can add water to so it would make a gravy but again he won't eat that much. I even heat his food.

I even just bought a new food this weekend **** Van Patten's Nature's balance to try mixing it with the Merrick puppy plate (dry) and still not eating. He did eat in the begining if I put the food directly on the food but that has stopped. I even went and bought baby food to mix with the dry but he won't eat it. I did try just the wet food but he turned his nose up at that.

He's not losing weight and we research everything that we give him but he just won't eat. Oh he will eat raw carrots and his treats but not his food. He has gained weight and is active and funny but won't eat. I put the food down at 8 AM and pick it up again about 30 minutes later. I also feed him again between 4-5 again picking up what he doesn't eat. He seems like he would do better if I just let it stay down (dry) and let him pick but I was told that was bad. He is teething and lost his bottom teeth so I was wondering if this could be the reason he's not eating? How long will it take to pass before he starts to eat again.

He's been to the vet and we started Frontline on him about 3 weeks ago was his first dose. Could this be the cause? He is also to start heartworm meds on April first but now I'm reading that this could cause him not to eat also. What do I do.

He is the perfect pup and I just want to do the best for him. I'm crazy about this puppy. He goes poop about 3-4 times a day and it's always normal. I even tried all different plates and bowels. Nothing works.

Robin