Coentrao last played for his country against Denmark in October 2015 and since then has suffered injuries and a loss of form, making only three league appearances for Real Madrid last season.
Since joining Sporting on loan, however, he has been playing regularly.
"I don't see any issue with Fabio Coentrao," said Portugal coach Fernando Santos.
"To say he has had a difficult time is a matter of opinion. Fabio is an experienced player and I've always said it's important to have players who know what I want from them."
"He's always been part of this team."
Portugal, who host Faroe Islands on Aug. 31 and visit Hungary three days later, are second in European Group B with 15 points from six games, three behind Switzerland who have won all their games.
Portugal host the Swiss in October in what Santos predicted would be the decisive match with only the winners of the six-team group qualifying directly for the World Cup in Russia next year.
"I don't believe that Switzerland will lose points, so we have to win our last four games," he said. "I'm convinced we will guarantee direct qualification."
Goalkeepers: Beto (Goztepe), Bruno Varela (Benfica), Rui Patricio (Sporting).
Defenders: Bruno Alves (Rangers), Cedric Soares (Southampton), Eliseu (Benfica), Fabio Coentrao (Sporting), Joao Cancelo (Inter), Jose Fonte (West Ham), Pepe (Besiktas).
Midfielders: Adrien Silva (Sporting), Andre Gomes (Barcelona), Danilo Pereira (Porto), Joao Mario (Inter), Joao Moutinho (AS Monaco), Pizzi (Benfica), William Carvalho (Sporting).
Forwards: Andre Silva (AC Milan), Bernardo Silva (Manchester City), Bruma (RB Leipzig), Cristiano Ronaldo (Real Madrid), Gelson Martins (Sporting), Nelson Oliveira (Norwich), Ricardo Quaresma (Besiktas)
(Writing by Brian Homewood; Editing by Clare Fallon)
