Layvin Kurzawa and Lucas Ocampos scored either side of the break to give Monaco a 2-0 win at Toulouse on Sunday in Ligue 1, but that victory now means that Falcao, who cost the principality club £55m in the summer, has just two goals from his last six outings.
"Everything is fine with Falcao," Ranieri told reporters. "I spoke to him after the game.
"We have three games this week and he will play in all of them. He will continue to play and will get his rhythm back again - he still needs time to find that."
Falcao has nine goals in Ligue 1 this season.