Studies of Nicotiana glauca show it can be used as a treatment for nicotine addiction since it does not contain nicotine are ongoing. Nicotiana glauca's active ingredient is anabasine--an alkaloid similar to nicotine. The active ingredient Anabasine can curb the desire for the cigarette by fooling the body into thinking is has had one, while you skip the withdrawals you would normally feel with nicotine. In additon you can feel a sense of euphoria.
Smoking the leaves of the nicotiana glauca plant have been said to curb addictions as strong as heroine on top of being somewhat hallucinogenic.