I have a cat that has had 2 severe uppers over her lifetime. She now is always snotty. We take her into the bathroom with us when we shower so she can benefit from the humidity. We also give lysine. We don't see any change in her condition.
My experience shouldn't prevent you from trying it though. It isn't terribly expensive so it won't hurt to try
"He is your friend, your partner, your defender, your dog. You are his life, his love, his leader. He will be yours, faithful and true, to the last beat of his heart. You owe it to him to be worthy of such devotion."