Codeine syrup is a liquid medication that contains codeine, an opioid used to relieve pain and suppress cough. It is often prescribed for conditions like severe coughs or pain that do not respond to over-the-counter medications. The syrup is typically taken by mouth and can be found in various formulations, sometimes combined with other ingredients like guaifenesin to help with mucus. Due to its opioid nature, codeine syrup can be habit-forming and may cause side effects such as drowsiness, constipation, or nausea. It is important to use this medication only as directed by a healthcare professional to minimize risks and ensure safe use.