Is compulsive lying as addictive as drugs or alcohol?

Lying: Yes. And very dangerous.

Not addicting but: Very habitual in some folks to the point that their lives are seriously damaged by the behavior. There are many reasons for that behavior including low self esteem, antisocial personality disorder, inability to ever be wrong and in some people just for the sheer thrill of doing it. Once the habit is well established it is hard to correct unless one admits to it and gets help.