The word "toco-lysis" is a derivative of the Greek words toketos, which means labor and lysis, which means, Òto bring to an end.Ó Together they mean the process of ending labor. Over the years, a number of drugs were used to achieve tocolysis. The most commonly used tocolytics are Indomethacin, Procardia, Terbutaline, Ritodrine and Magnesium Sulfate. At KOFINAS PERINATAL, after 25 years of experience with all kinds of tocolytics, we have developed a protocol for outpatient treatment by using Indomethacin and Procardia in various combinations according to the patient's particular condition. Rarely, and only, if we have absolutely no other choice, do we use hospitalization with Magnesium Sulfate. Terbutaline and Ritodrine have never convincingly shown that they can successfully prevent preterm delivery. On the contrary, chronic use of Terbutaline may cause increased irritability of the uterus due to its stimulation of the enzyme cAMP - phosphodiesterase.