The werewolves of the Ghostbusters universe do not seem to be the slobbering mangy monsters of old movies and pop culture, but rather intelligent people who have the ability to change into a wolf at will when the moon is full.
Werewolves are encountered in the episode "No One Comes to Lupusville" and in this episode, they are at first shown to be prisoners of Gregor, the rogue vampire who drove them underground and stole their homes from them, threatening the peaceful existence both vampires and the werewolves who lived there prior had established. He keeps them in the jail cells beneath city hall and attempts to use them to kill the Ghostbusters when the other vampires descend upon Lupusville to free the residents and drive Gregor out. The werewolves, now free and with the help of the moon, turned against Gregor and his followers.
The werewolves did not seem to be dangerous towards normal humans and even in their shifted state, appeared to possess the full mental and emotional controls of their human sides. Also, their werewolf forms are much larger than normal wolves and are quadrupeds with no tail but they do have a long muzzle filled with sharp fangs.
While not stated explicitly, it is implied that a normal human can become a werewolf via a bite, the same as the vampires.
During the Battle of Lupusville, the werewolves fought with the Ghostbusters and the good vampires to drive out Gregor and his followers so that they could take their town back and live in peace.
Interestingly, during the fight, several werewolves and vampires cross-bit each other, each turning the other into a vampire/werewolf or werewolf/vampire hybrid with the traits of both creatures often to the shock of the one being turned.
The Ghostbusters leave town before the end of the battle is shown, running for their lives, so it is implied that after they seal the town off with water, preventing the vampires from escaping, that the remaining werewolves and good vampires and the new hybrids made peace and continued living in the secluded town.
It is unknown if Gregor survived, but it is unlikely he lasted long considering that most of the towns people and his former vampire clan members were both out to get him.