Problem w dog going outside

Question
My dog has been with us for 2 years.  He is a Lab. He had been going outside to the bathroom OK but recently he won't go outside but to my knowledge he's not going in the house either.  I think he's holding pee and poop in.  I've been outside with him and I haven't seen him go poop for at least three days and pee in two days.  What's going on?  This can't continue.  he was a drop-off in our neighborhood so I kept him but don't know of his upbringing. He was about 1 yr when he arrived.

Answer
Carole, if you're certain that he hasn't eliminated in 2 days, please get him to the vet tomorrow.  He might have some sort of blockage that could be very dangerous.  I'd want to be sure to rule out anything medical before assuming it's a behavior issue.  Your vet may also have recommendations on how to relieve the constipation if he determines that's what needs to be done.

Do you have any idea whether he was frightened by something outside in the past week? He might have been startled by a loud sound or animal in the area.  You might try taking him on a walk to stimulate his system, allowing him to smell other dog smells and hopefully he'll want to mark some territory.  

You could also play a favorite game in the backyard to create a pleasant association with being out there again.  Does he like to fetch or chase a frisbee?  

It's hard to tell without seeing him in the environment, so I hope my suggestions can help a bit.  But, please, make sure there's nothing ailing him first!  Good luck.