Obesity is a condition in which excess body fat has accumulated to the high extent that may have adverse effects on health. Obesity may lead to reduced life quality and expectancy. Besides, it may cause serious health problems. Several anorectic anti-obesitic drugs have been developed with quite a few entering clinical trials. Currently, there are only two drugs (sibutramine and orlistat) commercially available. Drugs acting on endocannabinoid system (EC) were expected to be successful on preventing weight gain. Rimonabant was the first to be on market in 2006. However, the drug's approval has been withdrawn in 2008 due to its adverse effects, especially of its potential to cause psychiatric disorders. Other trials on EC inverse agonists or antagonists have also been suspended for now mostly for regulatory issues. This review will focus on anti-obesitic drugs affecting on EC and their toxicological outcomes. The suspension of clinical trials on these drugs will also be discussed.