It is on the World Health Organizations List of Essential Medicines. Codeine occurs naturally and makes up about 2% of opium. Medical uses
Pain
Codeine is used to treat mild to moderate pain. It is commonly used to treat post-surgical dental pain.Weak evidence indicates that it is useful in cancer pain, but it may have increased adverse effects, especially constipation, compared to other opioids. The American Academy of Pediatrics does not recommend its use in children due to side effects. The FDA lists age under 12 years old as a contraindication to use. Cough
Codeine is used to relieve coughing. Evidence does not support its use for acute cough suppression in children. In Europe, it is not recommended as a cough medicine in those under 12 years of age. Some tentative evidence shows it can reduce a chronic cough in adults. Diarrhea
It is used to treat diarrhea and diarrhea-predominant irritable bowel syndrome, although loperamide (which is available without a prescription for milder diarrhea), diphenoxylate, paregoric, or even laudanum are more frequently used to treat severe diarrhea. Formulations
Codeine is marketed as both a single-ingredient drug and in combination preparations with paracetamol (as co-codamol: e.g., brands Paracod, Panadeine, and the Tylenol-with-codeine series, including Tylenol 3 and 1, 2, and 4); with aspirin (as co-codaprin); or with ibuprofen (as Nurofen Plus). These combinations provide greater pain relief than either agent alone (drug synergy). Codeine is also commonly marketed in products containing codeine with other pain killers or muscle relaxers, as well as codeine mixed with phenacetin (Emprazil with codeine No.
Rapper Pimp C, from the group UGK, died from an overdose of this combination.Codeine is used in illegal drug laboratories to make morphine. Detection
Codeine and its major metabolites may be quantitated in blood, plasma or urine to monitor therapy, confirm a diagnosis of poisoning or assist in a medico-legal death investigation. Drug abuse screening programs generally test urine, hair, sweat or saliva. Many commercial opiate screening tests directed at morphine cross-react appreciably with codeine and its metabolites, but chromatographic techniques can easily distinguish codeine from other opiates and opioids. It is important to note that codeine usage results in significant amounts of morphine as an excretion product. Furthermore, heroin contains codeine (or acetyl codeine) as an impurity and its use will result in excretion of small amounts of codeine. Poppy seed foods represent yet another source of low levels of codeine in ones biofluids. Blood or plasma codeine concentrations are typically in the 50–300 µg/L range in persons taking the drug therapeutically, 700–7,000 µg/L in chronic users and 1,000–10,000 µg/L in cases of acute fatal over dosage.Codeine is produced in the human body along the same biosynthetic pathway as morphine. Urinary concentrations of endogenous codeine and morphine have been found to significantly increase in individuals taking L-DOPA for the treatment of Parkinsons disease. Legal status
Around the world, codeine is, contingent on its concentration, a Schedule II and III drug under the Single Convention on Narcotic Drugs.