Morphine Lidocaine

Lidocaine Morphine Ondansetron Pravastatin Procainamide Ranitidine Sumatriptan Vigabatrin ... 

Extracted benzoylecgonine, cocaine, diphenhydramine, ephedrine, lidocaine, morphine, nordiazepam, norpropoxyphene, nortriptyline Also analyzed amitriptyline, ampheteunine, codeine (different gradient), meperidine... 

Elimination of many drugs (eg, acetaminophen, many antibiotics, caffeine, lidocaine, morphine, phenytoln, and theophylline) is prolonged in neonates. For example, the half-life of caffeine Is approximately 3 hours in adults but may be greater than 100 hours In newborns. 

Once absorbed, foreign compounds may react with plasma proteins and distribute into various body compartments. In both neonates and elderly human subjects, both total plasma-protein and plasma-albumin levels are decreased. In the neonate, the plasma proteins may also show certain differences, which decrease the binding of foreign compounds, as will the reduced level of protein. For example, the drug lidocaine is only 20% bound to plasma proteins in the newborn compared with 70% in adult humans. The reduced plasma pH seen in neonates will also affect protein binding of some compounds as well as the distribution and excretion. Distribution of compounds into particular compartments may vary with age, resulting in differences in toxicity. For example, morphine is between 3 and 10 times more toxic to newborn rats than adults because of increased permeability of the brain in the newborn. Similarly, this difference in the blood-brain barrier underlies the increased neurotoxicity of lead in newborn rats. 

Rowbotham, M. C., Reisner-Keller, L. A., Fields, H. L. Both intravenous lidocaine and morphine reduce the pain of postherpetic neuralgia, Neurology 1991, 41, 1024-1028. 

If a drug undergoes an extensive first-pass metabolism (e.g., morphine, metoclopramide, ergotamine, or lidocaine), rectal administration may produce an even higher plasma level. The prolonged rectal administration of multiple drugs may produce local irritation or even rectal ulceration. 

MI usually develops after rupture or erosion of an atherosclerotic plaque within a coronary blood vessel. At this site, the clotting cascade is activated and the resultant thrombus occludes the lumen. In all patients under suspicion of MI, immediate therapy has to be initiated by the emergency physician. To relieve the patient from severe pain and anxiety, morphine and a benzodiazepine need to be given. Antiplatelet drugs and heparin are necessary for preventing further formation of thrombi. Nitroglycerin can be used to reduce cardiac load. When blood pressure and heart rate have stabilized, a p-blocker can be administered to lower cardiac 02 consumption and the risk of arrhythmias. Infusion of lidocaine is required to counter the threat of arrhythmias. The chance of survival of the MI patient depends on the interval between the onset of infarction and the start of therapy. 

Rectal absorption is generally slower than oral absorption, but for some drugs, rectal absorption exceeds oral absorption presumably due to avoidance of first-pass metabolism after rectal delivery. This has been reported for morphine, metoclopramide, ergotamine, lidocaine, and propranolol. Human rectal systemic availability of the extensively metabolized drug lidocaine is 65% as compared to 30% after oral administration.f ... 

The use of a continuous epidural infusion of lidocaine 0.4% plus fentanyl 1 pg/ml in combination with intravenous metamizol 40 mg/kg provided significantly better analgesia than epidural morphine 20 pg/kg plus intravenous metamizol 40 mg/kg during the first 3 postoperative days in 30 children undergoing orthopedic surgery, without increasing the incidence of adverse effects however, the difference in beneficial effect was small (70). 

Reinoso-Barbero F, Saavedra B, Hervilla S, de Vicente J, Tabares B, Gomez-Criado MS. Lidocaine with fentanyl, compared to morphine, marginally improves postoperative epidural analgesia in children. Can J Anaesth 2002 49(1) 67-71. 

A synergistic interaction of intrathecal fentanyl 100 pg and morphine 0.5 mg, given before induction, with systemically administered lidocaine 200 mg 4 hours later for ventricular tachycardia, resulted in potentiation of opioid effects in a 74-year-old man with major heart disease after coronary artery bypass grafting during the 5 minutes after lidocaine he had a respiratory arrest with loss of consciousness and miotic pupils, all reversed by naloxone (80). The proposed mechanism was thought to be a reduction in calcium ion concentrations in opioid-sensitive CNS sites. 

In 52 patients who received either epidnral bupivacaine (0.10-0.28 mg/kg/honr) or lidocaine (0.44-0.98 mg/kg/ honr), both with epidnral morphine, there were no significant differences in the times to mobilize, motor function (as measnred by the Bromage grade), and the incidence of hjq)otension (112). Most of the patients had no motor blockade, and the Bromage grade did not help predict which of them could be mobilized. 

Opioids potentiate the analgesic effect of neuraxial local anesthetics, with minimal adverse effects (SEDA-18,141) (SEDA-20, 121) (SEDA-22, 135), as shown in several studies with clonidine, fentanyl, morphine, or pethidine as the systemic or neuraxial analgesic, and bupivacaine, lidocaine, and ropivacaine as the local anesthetic. The benefits have been shown in relief of long-term pain and postoperative pain, in adults and children (SEDA-18, 141) (SEDA-18,146). 

Rygnestad T, Zahlsen K, Bergshen O, Dale O. Focus on mobilisation after lower abdominal surgery. A doubleblind randomised comparison of epidural bupivacaine with morphine vs. lidocaine with morphine for postoperative analgesia. Acta Anaesthesiol Scand 1999 43(4) 380-7. 

Postoperative analgesia from morphine has been shown to be the most effective if administered at the completion of the procedure (Brandsson et al 2000, Reuben et al 2001, Tetzlaff et al 2000). In these cases, it appears that the postoperative use of morphine allows the clinician to reduce both the level and the duration of other analgesics. This is not to say that the only potential benefit of morphine is in the postoperative patient. Morphine has also been shown to be of equivalent effect to corticosteroid administration in other forms of chronic arthritides (Keates et al 1999, Stein et al 1999). The reductions in inflammatory cell influx, reduced edema formation and analgesia provided with minimal systemic effects make intraarticular morphine a very attractive postoperative therapy. I most commonly use a combination of 5-15 mg morphine with 6 mg lidocaine for postoperative analgesia and have seen no untoward effects. The beneficial effects with respect to improved analgesia and ability to reduce the usage of NSAIDs remains to be proven. 

Clinically important, potentially hazardous interactions with acenocoumarol, alfuzosin, aminophylline, anisindione, anticoagulants, buprenorphine, butorphanol, caffeine, carmustine, dobazam, cocoa, dicumarol, dofetilide, duloxetine, epirubicin, eszopiclone, fentanyl, floxuridine, fluorouracil, galantamine, gliclazide, hydromorphone, itraconazole, ketoconazole, lidocaine, meptazinol, midazolam, mizolastine, modobemide, morphine, narcotic analgesics, oxprenolol, oxycodone, pentazocine, phenytoin, posaconazole, prednisone, propranolol, sufentanil, tolazoline, warfarin, xanthines, zaleplon, zofenopril, zolmitriptan, zolpidem... 

Hays, P.A. Lurie, I.S. Quantitative analysis of adulterants in illicit heroin samples via reversed phase HPLC. J.Liq.Chromatogr., 1991, 14, 3513—3517 [also acetylcodeine, acetylmorphine, aspirin, ben-zocaine, caffeine, chloroquine, diamorphine, diazepam, diphenhydramine, dip3rrone, lidocaine, meth-aqualone, monoacetylmorphine, morphine, nicotinamide, noscapine, papaverine, phenacetin, pheno-barbital, phenolphthalein, N-phenyl-2-naphthylamine, salicylic acid, strychnine]... 

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