Langston recommends the same tests as Krauter and Rubinstein, but she adds that if nothing's found, try drugs that will tighten the sphincter muscle. There are two I commonly use. Some young women who were taking the drug were having strokes, she says. But they were taking it in high doses, not in low doses. If that doesn't work, options from there are somewhat limited.
People are very creative.
It takes up a lot of time, but if you're going to be cleaning the carpets all day long, you could try diapering. It comes with a video and instruction booklet that states you only need to adhere it to the dog's collar when he gets carried away. I only wish I had e-mailed you a year ago, when we adopted him from the shelter. By the way, it's officially known as a citronella bark collar. And they can be purchased in most pet stores.