- Molecular NameCodeine
- SynonymCodeine anhydrous; L-Codeine; Methylmorphine; Morphine monomethyl ether; Norcodeine, N-Methyl; Norcodine, N-Methyl
- Weight299.37
- Drugbank_IDDB00318
- ACS_NO76-57-3
- Show 2D model
- LogP (experiment)1.14
- LogP (predicted, AB/LogP v2.0)1.09
- pka8.2
- LogD (pH=7, predicted)-0.14
- Solubility (experiment)9.04 mg/ml
- LogS (predicted, ACD/Labs)(ph=7)-0.97
- LogSw (predicted, AB/LogsW2.0)6.07
- Sw (mg/ml) (predicted, ACD/Labs)1.64
- No.of HBond Donors1
- No.of HBond Acceptors4
- No.of Rotatable Bonds1
- TPSA41.93
- StatusFDA approved
- Administrationoral, intra-rectally, SC, IM
- PharmacologyAn opiate used for its analgesic, antitussive, and antidiarrheal properties.
- Absorption_value95.0
- Absorption (description)Well absorbed after oral administration, with peak plasma levels occurring after about 1 h
- Caco_2N/A
- Bioavailability50.0
- Protein binding16.0
- Volume of distribution (VD)2.6 L/kg
- Blood/Plasma Partitioning ratio (D_blood)N/A
- MetabollsmMetabolised in the liver by O-demethylation involving P450 isoenzyme CYP2D6 to form morphine, N-demethylation to form norcodeine, and conjugation to form glucuronides and sulfates of both unchanged drug and its metabolites.
- Half life2.9 h
- ExcretionAfter an oral dose, about 86% is excreted in the urine in 24 h; of the excreted material, 40 to 70% is free or conjugated codeine, 5 to 15% is free or conjugated morphine, 10 to 20% is free or conjugated norcodeine, and trace amounts may be free or conjugated normorphine; some of the dose is excreted in the bile and trace amounts are found in the faeces; unchanged drug accounts for 6 to 8% of the dose in urine in 24 h but this may increase to about 10% when the urinary pH is decreased. After an intramuscular dose, 15 to 20% is excreted unchanged in acid urine in 24 h. Small amounts of hydrocodone, norhydrocodone, 6α-hydrocodol, and 6β-hydrocodol have also been detected in urine.
- Urinary ExcretionNegligible
- Clerance11 ml/min/kg.
- ToxicityThe estimated minimum lethal dose is 800 mg, but codeine is much less toxic than morphine and death directly attributable to codeine is rare; in most fatalities involving codeine, other drugs and/or alcohol is also present. Drug addicts may use doses up to 10 times normal before showing toxic effects, whilst children may show toxicity with only 1/20th of the dose.
- LD50 (rat)LD50=1178 (peroral); LD50=365 (subcutaneously)
- LD50 (mouse)LD50=574 (peroral); LD50=271 (subcutaneously)