Codeine is an FDA-approved medication; it belongs to the opioid drug class. This medication is used for the treatment of chronic back pain. Also, it is commonly used to treat mild to moderate pain and coughing. Codeine 15mg, 30mg, 60mg, and 300-30mg are the common dosage that is prescribed to patients. This medication is available in different forms, including tablets, capsules, and liquid forms.