dog behavior

Question
My 8 yr. old Lhaso poops in the car everytime I take him to the vet or groomer even if in a crate.  Is there a safe way to sedate this 23 lb. dog so that I can get his care without having to destroy my car?

Answer
I don't understand why the dog would need to be sedated at all. If you sedate him he will still poop but it will be runny and get all over him.
Unless the dog is vicious, sedation doesn't help for soiling a crate.

Maybe walk him first before you put him in the crate. If all else fails, ask your vet about sedation or something else.

I also wonder is this a new problem or have you been dealing with it for 8 years? It's hard to break a habit like that now after so long. Some dogs just get sick in a car and some never do.
Defecating is just his way of being scared.