Discoloration of White coat

Question
I used Frontline Flea/Tick on my puppy 2 weeks ago, he now has a dark/yellow coloration down his spine and around his ears. Could this be due to the medication? If so what can I use that does not cause discoloration?

Answer
I have never heard of Frontline causing coat discoloration.

You don't say how old your puppy is, but I suspect he might be growing in his second coat which becomes evident in some dogs after three months of age. It is not uncommon for some white dogs to have yellow or tannish coloration down their backs.