The 24-year-old joined from Sao Paulo last August but has failed to make any kind of impact at Camp Nou.
The Brazilian has been limited to only one Liga appearance and three Copa del Rey games - coming on as a substitute twice - and has rarely been named on the bench either.
Douglas' representative, Marcos Casseb, is disappointed with the way the player has been treated, but says he will not be looking for a way out of Catalunya any time soon.
"They're being unfair with Douglas," Casseb told RAC1. "But we have no intention of leaving Barcelona."
Douglas joined Barca for an initial fee of €4 million from the Brazilian club.