"He should go for a treatment," Valcke said when asked by reporters about the Suarez case. "I don't know if it exists but he should do something by himself because it's definitely wrong."
Valcke welcomed the ban on Suarez from playing for Uruguay for nine competitive matches and from all football-related activity for four months after he bit Italy defender Giorgio Chiellini in a World Cup match on Tuesday (local time).
"If it's the first time, it's an incident. More than once, it is not any more an incident. That is why also the sanction, it has to be exemplary."
Suarez flew back to Uruguay on Friday to a hero's welcome led by the country's president Jose Mujica.
Valcke said FIFA was concerned about the impact of the images of Suarez biting an opponent on football fans worldwide, including children.
"It was seen by hundreds of millions of people. It is not what you want your kids, what you want the little (ones) who are playing football around the world, to see at a World Cup," he told journalists at FIFA's daily tournament media briefing.
Valcke brushed aside a suggestion from a reporter that the ban was unfairly punishing Suarez's club Liverpool, with whom he cannot even train until late October.
"It is not Liverpool who is punished. It is the player who is punished and what he did has not only happened in international games," he said.
"So the Disciplinary Committee took into consideration the past events and the past behaviour of Luis Suarez and that is why they made their decisions."
Suarez served a 10-match ban last year, while at Liverpool, after biting Chelsea's Branislav Ivanovic in a Premier League match. In 2010 he was suspended for seven games for biting PSV Eindhoven's Otman Bakkal while playing for Ajax Amsterdam.
