Koenig’s family reported the actor missing about a week after he failed to board a flight back to the United States from Vancouver on February 16.
The actor was said to be staying with friends for a few days, although his family has been worried because he had seemed withdrawn and despondent in recent weeks.
Police in Vancouver are investigating the matter and several celebrities are reaching out online to try and locate Koenig, including Sarah Silverman and Alyssa Milano.
MTV News reported that Koenig had been suffering from depression, citing statements from both family and law enforcement.
The Growing Pains actor had recently turned down an offer to work on a film project, raising the suspicions of a frequent collaborator that something was wrong.
Koenig’s father, Walter, an actor himself who appeared in the original “Star Trek”, said that Andrew’s disappearance was unlikely drug-related.
Anyone who has spotted Koenig or has information on his whereabouts is encouraged to contact Vancouver police at 604-717-2534.