A literature review and meta-analysis suggests that cytisine is effective for smoking cessation.

Cytisine has been used in Europe for the past 40 years in the treatment of tobacco dependence. For various reasons, a potentially effective treatment for a condition that causes considerable morbidity and mortality in developed countries has remained unnoticed and unpublished in English-language literature.

Cytisine is an alkaloid found in all parts of Cytisus laburnum, the golden rain tree. For decades it has been used as a smoking cessation drug in Eastern Europe, and marketed by a Bulgarian firm as Tabex (http://www.tabex.net)

Cytisine has a molecular structure similar to nicotine and acetylcholine and is an agonist of nicotinic receptors.

Toxicity remains uncertain and the results need the confirmation by state-of-the-art clinical trials.

The question is inevitably raised, how many effective drugs have remained unnoticed because they were not published in English in Western countries?