Plasma morphine

Various dilutions of unknown plasma, morphine-6-antiserum, 3H-dihydromorphone are prepared afresh,... 

Conversion from Avinza to other pain control therapies - It is important to remember that the persistence of Av/> za-derived plasma morphine concentrations may be in excess of 36 hours when making a conversion to other pain control therapies. 

Therapeutic Concentration. Because of its rapid hydrolysis, diamorphine is difficult to detect in plasma. Morphine plasma concentrations are usually in the range 0.01 to 0.07 pg/ml. Diamorphine was detected in blood 2 minutes after an intravenous dose of 4 to 5 mg given to 4 subjects, but declined to a blood concentration of less than 0.01 pg/ml within 10 to 15 minutes (C. E. Inturrisi et al.. New Engl. J. Med., 1984, 310,1213-1217). 

Although not routinely given by the buccal or sublingual routes, several research studies have shown that absorption of morphine from the mouth gives rise to effective analgesia and that these routes may provide suitable alternatives to parenteral administration. " Clinical studies have suggested that the bioavailability of morphine is 40-50% greater after buccal than intramuscular administration as plasma morphine... 

Two men, aged 87 and 65 years, both with renal insufficiency, took oral morphine 30 mg/day for pain management (30). While the 65-year-old tolerated morphine well despite a high plasma morphine-6-glucuronide concentration of 1735 nmol/1, the 87-year-old had severe sleepiness and drowsiness, even though the plasma morphine-6-glucuronide concentration was only 941 nmol/1. 

Tighe KE, Webb AM, Hobbs GJ, Persistently hi plasma morphine-6-glucuronide levels despite decreased hourly patient-controlled andgesia morphine use after single-dose diclofenac potential for opioid-related toxicity. Anesth Amlg ( 999) 88,1137-42. 

Quinidine sulfate 600 mg, given one hour before intravenous morphine sulfate 150 mierograms/kg, did not alter morphine-induced miosis in healthy subjects. However, the same dose of quinidine given before oral morphine sulfate 30 mg (with ondansetron as an antiemetic) increased morphine-induced miosis by 56%. This increase was considered proportionate to the increase in morphine AUC (60%) and maximum level (88%). There was no change in the elimination half-life of morphine. Similarly, in another study in healthy subjects, quinidine 800 mg, given one hour before intravenous morphine 7.5 mg did not alter the respiratory depressant nor mitotic effects of morphine, and there was no change in plasma morphine or morphine glucuronide levels. ... 

Susceptibility factors Genetic Rapid metabolism of a dose of codeine within the recommended limits resulted in high plasma morphine concentrations, resulting in death in a 2-year-old boy who was given codeine syrup postoperatively following adenotonsillectomy [66 ]. The authors suggested that the ultrarapid metabolizer phenotype had been the main contributor to the occurrence of bronchopneumonia,... 

Application of the Extractive Alkylation Technique to the Pentafluoro-benzylation of Morphine and Surrogates, with Special Reference to the Quantitative Determination of Plasma Morphine Levels Using Mass Fragmentography... 

Combined morphine/naltrexone capsules have shown comparable analgesia, adverse effects and bioequivalence to a similar morphine sulfate extended-release capsule product (Kadian ) with regard to rate and extent of plasma morphine absorption [8]. In the clinical efficacy trial in patients with pain due to osteoarthritis, change in the weekly BPI average pain score was statistically significantly superior for those treated with Embeda as compared to placebo. A review of the Subjective Opiate Withdrawal Scales (SOWS)... 

Combined morphine/naltrexone capsules are to be swallowed whole or the contents of the capsules sprinkled on apple sauce and the pellets in the capsules are not to be crushed, dissolved, or chewed. A pK study of combined morphine/naltrexone crushed vs. whole was done to compare the plasma concentrations and relative bioavailability of morphine, naltrexone, and the major naltrexone metabolite (6-P-naltrexol). Plasma morphine levels from crushed morphine/naltrexone capsules showed no extended-release properties. While concurrent administration of high-fat food decreased the rate and extent of morphine absorption from combined morphine/naltrexone, the total bioavailability or sequestration of naltrexone was not affected. An alcohol effects study examined the bioavailability of combined morphine/naltrexone when dosed under fasting conditions with 4%, 20% and 40% alcohol compared to water. The rate and extent of bioavailability and total exposure to morphine (AUC, C ) were not affected when the drug was adminis-tered concomitantly with either 4% or 20% alcohol, when compared to administration with water. When combined morphine/naltrexone was administered with 40% alcohol (240 mL over 15 minutes), the rate and extent of bioavailability (C ) doubled and the t was 5 hours earlier, when compared to administra-tion with water. The total systemic exposure to morphine (AUC) was not affected [9]. 

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