They have issued a statement saying that they are going to offer the Liverpool striker anger management counselling, following the furore over his biting of Branislav Ivanovic on Sunday.
"It was not good to see to say the least. It was unacceptable," said PFA chief executive Gordon Taylor.
"His reputation for controversy continues to increase when he can be such a good player, one of the world's best, so it is a real dilemma now.
"It's uncalled for, it's not good, it's depressing, it's such a shame for a player who's a really good footballer but this is not the first time that such things have happened.
"I know it's a really difficult one for Liverpool and the FA are going to have to deal with it.
"There's physical contact, emotions run high but no matter what players these days have to be considered as role models for youngsters.
"It was such a good game, great comeback, but this will take all the headlines.
"It doesn't make it better when things have happened before and they're repeated again.
"You begin to wonder 'is he going to learn his lesson?' Because when his football shines through he's so highly regarded so it's just a big shame."
The FA are still to decide on what punishment to hand out for the incident.
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