phenergan should not be used in pediatric patients less than 2 years of age because of the potential for fatal respiratory depression. postmarketing cases of respiratory depression, including fatalities, have been reported with use of phenergan in pediatric patients less than 2 years of age. Off-label prescribing refers to the use of medication for a condition not named in its FDA approval. Off-label prescribing has come under fire of late, because some large drug companies have been. Off Label Use while taking Promethazine. About Promethazine. 4.2? 24,360 Discussions. Promethazine is an antihistamine and a nausea & vomiting medication. Uses: Promethazine is taken to prevent Nausea and Vomiting and is mostly mentioned together with these indications. It is prescribed for Pain. In addition, Promethazine is used in Sedation. Read More. See more about. Promethazine Off. Treating nausea and vomiting related to surgery or anesthesia is among the approved uses for Phenergan. This eMedTV segment discusses these and other uses (including off-label purposes) and explains how this medication works for various conditions. Uses for the drug also include causing sedation before or after surgery and during labor. Occasionally, healthcare providers may recommend promethazine for off-label purposes, such as for the treatment of morning sickness, coughing, or nausea and vomiting related to gastrointestinal illness. Treating nausea and vomiting related to surgery or anesthesia is among the approved uses for Phenergan. This eMedTV segment discusses these and other uses (including off-label purposes) and explains how this medication works for various conditions. Off-label uses have not been formally evaluated, and evidence provided for one clinical situation may not apply to others. As an area of controversy, off-label use is subject to the contradictory. Prescribing drugs for unapproved uses, a practice you might see referred to as “off-label” prescription, is probably more common than you think. Researchers Have Found That More Than One Out Of Five Prescriptions Is Off-Label. Phenergan (promethazine) belongs to a group of drugs called phenothiazines. It works by changing the actions of chemicals in your brain. Promethazine also acts as an antihistamine. Find patient medical information for Phenergan Oral on WebMD including its uses, side effects and safety, interactions, pictures, warnings and user ratings.