Clomipramine causing odd behavior?

My dog was put on clomipramine 3 weeks ago for new separation anxiety.  I understand that for the first week he may feel "different" and that his behavior would reflect this, however, his behaviors are becoming more distrubing.
He does not eat or drink enough, he will not step off the back patio without a lot of coaxing, he pants constantly, and is more clingy than ever.  
I think that discontinuing the medication would be best but was just wondering if it may be the cause of the behavior.
Thanks

[Aleda M Cheng, D.V.M., C.V.A]

Clomipramine can cause a great variety of side effects including the ones that you have described.  This problem with clomipramine may be dose related or your dog may be especially sensitive to the medication.  It would be best to contact your prescriber about the side effects for a dose adjustment or to switch to another medication.