Morphine dosing

Equivalent po morphine dose = 45-134 mg/day. eFor breakthrough pain only. 

Another site of action for opioids is through the regulatory actions of the central nervous system (CNS) on the immune system. Substantial evidence supports the existence of a complex, bidirectional link between the CNS and the immune system (e.g., [65]). Experimental evidence indicates that morphine s immunomodulatory effects involve central opioid receptors. An initial study by Shavit and colleagues [12] found that systemic administration of morphine, but not N-methylmorphine (a form of morphine which does not readily penetrate the blood-brain barrier), produces a naltrexone-reversible suppression of splenic natural killer cell activity in the rat. That same study showed that intracerebroventricular (icv) administration of morphine dose-dependently suppresses... 

SR Administer one-half the patient s total daily oral morphine dose as Kadian every 12 hours or by administering the total daily oral morphine dose as Kadian every 24 hours. Kadian should not be given more frequently than every 12 hours. The first dose of Kadian may be taken with the last dose of any IR opioid medication because of the long delay until the peak effect after administration of Kadian. 

Tablets-A patient s daily morphine requirement is established using IR oral morphine (dosing every 4 to 6 hours). The patient is then converted to morphine ER in either of 2 ways ... 

Santillan, R., Hurle, M.A., Armijo, J.A., de los Mozos, R., Florez, J. Nimodipine-enhanced opiate analgesia in cancer patients requiring morphine dose escalation a double-blind, placebo-controlled study, Pain 1998, 76, 17-26. 

A survey of patients in hospices published in 1999 showed that none of the 55 patients receiving 300 or more milligrams of morphine a day for pain relief had difficulty breathing because of the drug. Survival times in hospice were not any different for those on these high morphine doses. 

Nakahara et al. studied the disposition of 6-AM in monkey and human hair. 6-AM and morphine were present in all hair samples, and heroin was not detected. In addition, the concentration of 6-AM was greater than the concentration of morphine. Nakahara et al. also evaluated the total morphine content (heroin and 6-AM were hydrolyzed to morphine) in monkey hair following subcutaneous administration of heroin (2.5 mg) and morphine (10 mg). Although the morphine dose was 4 times greater than the heroin dose, the mean morphine concentration was only about two thirds of that found following heroin administration. The results indicate that heroin and 6-AM are incorporated more readily into hair than morphine. Based upon this information, the theoretical distribution of heroin and its metabolites in hair is illustrated in Figure 6. 

A limited number of small single-dose studies have demonstrated that morphine metabolism is impaired in patients with decompensated cirrhosis, and half-life can be doubled. Information on multiple morphine doses in cirrhotic patients is lacking, but because of the demonstrated prolonged half-life in single-dose studies, accumulation could occur, and an increased dosing interval of approximately twofold is recommended in some reports. 

OPIOIDS RIFAMPICIN 1 effect of alfentanil, codeine, methadone and morphine Rifampicin t hepatic metabolism of these opioids (alfentanil by CYP3A4, codeine by CYP2D6, morphine unknown). Rifampicin is also known to induce intestinal P-gp, which may 1 bioavailability of oral morphine Be aware that alfentanil, codeine, methadone and morphine doses may need to be t... 

OPIOIDS OESTROGENS Effect of morphine may be 1 by combined oral contraceptives Hepatic metabolism of morphine ist Be aware that morphine dose may need to be t. Consider using an alternative opioid such as pethidine... 

Respiratory depression is seldom a problem with morphine dose escalated in this way. 

Yamaguchi H, Watanabe S, Motokawa K, Ishizawa Y. Intrathecal morphine dose-response data for pain rehef after cholecystectomy. Anesth Analg 1990 70(2) 168-71. 

The opioid dose required for analgesia will be affected by genotype variants. One dose does not fit all. For example, a patient with the variant of OPRMl may require twice the standard morphine dose to be effective. This variability in clinical effect among patients based on genotype emphasizes the need to perform pharmacogenetic assessments in patients, perhaps leading to the concept of pharmacogenetic-based dose adaptation [49]. 

Camphorated Dover s Powder. Pulverize 5 drachms camphor with ether, add 5 drachms prepared chalk, 5 drachms pulverized Itquonce, and 17 grains sulphate of morphine. Dose, from 1 to 10 grains, used in oU kinds of fevers, and as an anodyne. 

Later in the addiction period, the same dose of A -allylnormorphine evoked more intense syndromes, although the morphine dose schedule remained unchanged. As the daily dose level of morphine and the duration of addiction increased, smaller amounts of iV-allylnormorphine precipitated abstinence phenomena. After stabilization on 360 mg. of morphine per day or 140 mg. of methadone per day, severe abstinence syndromes were precipitated by 5 mg. of A -allylnormorphine. The most intense abstinence syndrome ever observed at the U.S. Public Health Service Hospital in Lexington occurred when 30 mg. of iV-allylnormorphine were administered subcutaneously to a subject who had been stabilized on 300 mg. of morphine per day. 

Dr HE said that she had only been on the ward for 2 months as part of her training to be a GP, and it was the first time that she had prepared a morphine dose for a baby. 

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