chihuahua sleeping issues

Question
I have a four year old mini chihuahua named Paco (weighs about 5 lbs).  He sleeps a lot.  He's the sweetest thing, never bites.  I'm not sure if he is lazy or if he's sick or depressed or bored or what.  He sleeps all night, in the bed with my wife and I.  He usually gets up briefly with me in the morning, and then he goes back to bed after I leave for work.  Except for a few brief visits with my wife through out the day, he sleeps (or at least lays alone) in a chair in our spare bedroom all day until I get home.  He usually is excited to see me when I get home... but after about a half hour to an hour, he's back in the spare bedroom for most of the evening until it is bedtime.  I estimate, without exageration, that he sleeps, or at least lays alone, for 18 hours a day.  I find this odd, and, honestly, disturbing.  I'm worried about him.  We have two cats, and, dispite being smaller than both of them, he's obviously higher in the "pack" than they are.  He plays with them, but they are very afraid of him when he's eating, so I don't think he's hinding out of fear or anything.  He has been neutered, and eats with a healthy appetite normally (he seems a bit under the weather at the moment... for the past three or four days... fleas have bitten him, and he's been stratching to the point that he's leaving whelps on himself... we're taking him to the vet in two days to get a check up and some frontline).  Could he possibly not be getting enough nutrition?  Would that make him listful or could be depressed... it seems his sleeping has gotten worse within the past six months... he's always napped a lot... but not quite as much as he is now.  Oh, he is potty trained, without flaw, to go on puppy pads... he's just so tiny that we didn't see much of a problem letting him use them, and he can't stand the cold in the winter outside.... he's lucky if he goes outside once a month.  Not sure if I have given enough information or too much, but I'm trying to include anything at all that I thought might be even remotely helpful.  Any information or assistance you could give would be greatly appreciated.  Thank you for your time and help.

Sincerely,

Josh & Paco

Answer
Hi Josh, I agree with you that the excessive sleeping may be a problem. Speak with your vet about his nutrition, body weight, fleas and internal parasites. Are there times during the day that he can go out for a walk, to get him slowly used to being active again. I see no problem with piddle pads, but dogs (like children) need outside time in the sun. He is young still and should have plenty of playtime. Speak to your vet about the possibility of depression as well.  Maybe adding nutritional paste or vitamin pastes to his daily diet, or vitamins, may help him resume normal activity. In the winter, there are some very economical and practical doggie coats that would help him enjoy going out. Do you take him for walks and drives with you?  Sometimes a dog can get depressed if the pack leader (you and your wife) are gone or long periods of time. Schedule plenty of play time with him once your vets gives him the all clear. Most of my chihuahua writers are asking questions about how to calm their pet down. Please leave feedback, nominations, and follow-up with any questions you may have. As volunteers we really like to know that we are making a difference in the lives of our online friends and their canine companions. It is easy to see the results at our school, but more difficult online. I am very concerned about your boy and would really appreciate it if you let me know what your veterinarian suggests. There are many things that can cause a dog to be lethargic, which is certainly is, so keep me posted. Thank you. Regards, Susan