Codeine dosage

Ko, C.Y. Marziani, F.C. Janicki, C.A. H -performance liquid chromatographic assay of codeine in acetaminophen with codeine dosage forms. J.Pharm.Sci., 1980, 69, 1081-1084... 

Detoxiflcation may be accomplished with phenobarbital (60 mg of phe-nobarbital for 500 mg of glutethimide). If concomitant codeine dependence is present (and this codependence should be strongly suspected), then methadone can be used adjunctively (10 mg of methadone for 120 mg of codeine) (Khajawall et al. 1982). Approximate sedative-hypnotic dosage equivalencies are listed in Table 3-5. 

Do not use oxycodone in children. Safe dosage of codeine has not been established for children younger than 3 years of age. Safety and efficacy have been established with remifentanil from birth to 12 years of age in maintenance of general anesthesia. 

Codeine and dihydrocodeine not to exceed 1800 mg/dL or 90 mg/tablet or other dosage unit... 

Not more than 1.8 grams of codeine per 100 milliliters or not more than 90 milligrams per dosage unit, with an equal or greater quantity of an isoquinoline alkaloid of opium. 

Dosages and routes of administration Codeine is used orally in single doses of 30 to 60 mg up to a total dose of 240 mg per day for pain relief. Codeine is used in the form of different salts such as hydrochloride, phosphate and sulfate. To increase the duration of action, slow-release preparations have been developed. Codeine is often combined with other analgesics e.g. acetyl salicylic acid or paracetamol. For cough inhibition lower doses are sufficient. 

Codeine was extracted from opium in 1832, and was the first partial success in the attempt to discover a safer and less addictive drug. However, with fewer side effects came a less potent analgesic. About 100 mg of codeine are needed to produce the same effect as 10 mg of morphine. It was believed at the time (and it is still debated) that codeine s milder effects on a per weight basis actually result in fewer side effects when equally effective dosages are given (i.e., 100 mg of codeine produces fewer side effects than 10 mg of morphine). For the most part, standard medical practice has been to prescribe codeine for moderate pain, and reserve morphine for more severe pain. 

The metabolism of morphine and related opiates has been investigated extensively and reviewed/424 426 It tends to be very rapid after parenteral administration but unpredictable after oral dosage. Scheme 2.26 illustrates the major metabolic pathways for morphine (1), codeine (2), and heroin (256). 

In potency, pethidine is graded between codeine and morphine (50-100 mg is equivalent to 10 mg morphine in man),(2) and it is useful for the management of mild to moderate pain, especially in patients intolerant to opioids. Its toxicity is relatively low and its duration of action is somewhat shorter than that of morphine. At equivalent dosage, pethidine is at least as depressant as morphine upon respiration and while morphinelike side effects such as nausea and vomiting frequently occur, it produces little disturbance of urinary function or bowel action. It is extensively used for the relief of labor pain even though it increases the incidence of delay on the first breath and cry of the neonate (3) several critical reports on the efficacy of the drug in obstetrics have been made.(4) Tolerance to pethidine develops slowly, and its dependence liability is claimed to be lower than that of morphine.(5) Full accounts of the clinical use of pethidine are available.(4,6)... 

Many examples of the effects of tablet excipients on dmg decompositions are reported in the pharmaceutical literature. Chemical interaction between components in solid dosage forms may lead to increased decomposition. Replacement of the phenacetin in compound codeine and ARC tablets by paracetamol in NHS formulations in Australia in the 1960s (because of the undesirable side-effects of phenacetin), led to an unexpected decreased stability of the tablets. The cause was later attributed to a transacetylation reaction between aspirin and paracetamol and also a possible direct hydrolysis of the paracetamol (Scheme 4.15). 

Codeine and dihydocodeine are opioid analgesics that act directly on opiate receptors in the brain, producing analgesia, respiratory depression, euphoria and sedation. They are weak narcotic analgesics, useful for the treatment of mild to moderate pain. Their major side-effect at non-prescription dosages is constipation. 

Alvi, S.U. Castro, F. A stability-indicating simultaneous analysis of acetaminophen and hydrocodone bitartrate in tablets formulation by HPLC. J.Liq.Chromatogr., 1987, 10, 3413-3426 [stability-indicating simultaneous impurities, acetaminophen, codeine, hydromorphone tablets column temp 30] Fatmi, A.A. Williams, G.V. Simultaneous determination of acetaminophen and hydrocodone bitartrate in solid dosage forms by HPLC. J.Liq.Chromatogr., 1987, 10, 2461—2472... 

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