Advantage II Flea Control

My 8 pound Pom-chi is on her second dose of Advantage II flea control and it's just now finally working. Unfortunately, two days ago I noticed a really foul urine smell coming from the site of the Advantage application (between the shoulder blades). I bathed her immediately, but it has been 10 days since the application and when dry, the smell remained in full force. This symptom is not included in the manufacturer's list of possible side effects- anyone experienced this with their pet? Does anyone know if this may be cause for alarm?

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

Stranger things have happened.  

To be definitive about the cause of the odor it might be best to try it one more time next month and see if the problem occurs next month.  If it does occur again,  than I recommend that you report this to the Advantage hotline number found on the box.