The content of synthetic cannabinoids (SC) which are known in Europe as Spice, in the U.S.A. as K2, and in Turkey as Bonsai or Jamaica is not standard. Also SC are known to contain approximately 400 chemical compounds which vary from country to country. SC mimics the effect of Δ9-tetrahydrocannabinol (THC) which is the major effective content of Cannabis or Marijuana by cannabinoid-1 (CB1) and cannabinoid-2 (CB2) receptors in the body cell. Although the new SC are synthesized and the number of new variants is increased in every day; JWH-018 among these variants exerts full agonist effect on both CB1 and CB2 receptors also it has a short-term effect as 2 hours. For this reason, JWH-018 is the most commonly used as SC. There are a few data in the literature regarding to the pharmacokinetic and pharmacodynamic effects of SC. Furthermore, most of the existing data are based on in vitro experiments. In the JWH-018 report, at Critical Review Report Agenda item 4.5 Expert Committee on Drug Dependence of World Health Organization (WHO), Thirty‐sixth Meeting Geneva, 16‐20 June 2014, is declared that despite a marked elevation of the heart rate is one of the clinical signs very often seen after intoxication with SC, there is no available study data regarding effects of SC on cardiovascular, respiratory, gastrointestinal, liver, kidneys and genitourinary systems. The aim of this review is to highlight cardiovascular effects of JW-018 which is considered to be the prototype for synthetic cannabinoids to prepare the ground for new work to be done.