: CODEINE is a opioid pain reliever used to treat mild to moderately severe pain. It is also used, usually in combination with other medications, to reduce coughing. Codeine is available as a single-ingredient product, or in combination with acetaminophen or aspirin, and in some cough and cold medications.Sometimes it may cause breathing problem. Try to concern your doctor before buying it.Codeine may cause sleepy sometimes.This medicine also available in tablet and syrups.