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**Medical Uses**

Codeine treats mild to moderate pain.
– Commonly used for post-surgical dental pain.
– Some evidence suggests efficacy in cancer pain.
– American Academy of Pediatrics advises against use in children.
– FDA contraindicates use in children under 12 years old.

**Pain Management**

– Used for mild to moderate pain.
– Commonly prescribed for post-surgical dental pain.
– Limited evidence supports its efficacy in cancer pain.
– Side effects may be more pronounced compared to other opioids.
– Not recommended for children due to potential adverse effects.

**Cough Relief**

– Relieves coughing.
– Not supported for acute cough suppression in children.
– Unrecommended for children under 12 years old in Europe.
– Tentative evidence shows efficacy in chronic cough in adults.

**Diarrhea Treatment**

– Used for diarrhea and diarrhea-predominant irritable bowel syndrome.
– Other medications like loperamide are preferred for severe diarrhea.
Codeine is effective but less frequently used for severe diarrhea.


– Marketed as single-ingredient and combination drugs.
– Combination with paracetamol, aspirin, or ibuprofen enhances pain relief.
– Available in various combinations with other painkillers or muscle relaxers.
– Prescription-only time release tablets are also available.
– Found in cough syrups and linctus for various indications.

Codeine (Wikipedia)

Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, Papaver somniferum. It is typically used to treat mild to moderate degrees of pain.[failed verification] Greater benefit may occur when combined with paracetamol (acetaminophen) or a nonsteroidal anti-inflammatory drug (NSAID) such as aspirin or ibuprofen. Evidence does not support its use for acute cough suppression in children or adults. In Europe, it is not recommended as a cough medicine in those under 12 years of age. It is generally taken by mouth. It typically starts working after half an hour, with maximum effect at two hours. Its effects last for about four to six hours. Codeine exhibits abuse potential similar to other opioid medications, including a risk of habituation and overdose.

Skeletal formula
Ball-and-stick model
Clinical data
Other names3-Methylmorphine
  • AU: A
Routes of
By mouth, rectal, subcutaneous injection, intramuscular injection
Drug classOpioid
ATC code
Legal status
Legal status
Pharmacokinetic data
BioavailabilityOral: ~90%
MetabolismLiver: CYP2D6 (to morphine), CYP3A4 (to norcodeine), UGT2B7 (to 3- and 6-glucuronides of codeine, norcodeine, and morphine)
• Others (e.g., conjugates)
Onset of action15–30 minutes
Elimination half-life2.5–3 hours
Duration of action4–6 hours
  • (5α,6α)-7,8-didehydro-4,5-epoxy-3-methoxy-17-methylmorphinan-6-ol
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.000.882 Edit this at Wikidata
Chemical and physical data
Molar mass299.370 g·mol−1
3D model (JSmol)
  • CN1CC[C@]23[C@@H]4[C@H]1CC5=C2C(=C(C=C5)OC)O[C@H]3[C@H](C=C4)O
  • InChI=1S/C18H21NO3/c1-19-8-7-18-11-4-5-13(20)17(18)22-16-14(21-2)6-3-10(15(16)18)9-12(11)19/h3-6,11-13,17,20H,7-9H2,1-2H3/t11-,12+,13-,17-,18-/m0/s1 ☒N
 ☒NcheckY (what is this?)  (verify)

Common side effects include vomiting, constipation, itchiness, lightheadedness, and drowsiness. Serious side effects may include breathing difficulties and addiction. Whether its use in pregnancy is safe is unclear. Care should be used during breastfeeding, as it may result in opiate toxicity in the baby. Its use as of 2016 is not recommended in children. Codeine works following being broken down by the liver into morphine; how quickly this occurs depends on a person's genetics.

Codeine was discovered in 1832 by Pierre Jean Robiquet. In 2013, about 361,000 kg (795,000 lb) of codeine were produced while 249,000 kg (549,000 lb) were used, which made it the most commonly taken opiate. It is on the World Health Organization's List of Essential Medicines. Codeine occurs naturally and makes up about 2% of opium.

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