Muscle rigidity morphine

Morphine generally has sedative effects, reducing overall activity. But local injections into dopaminergic systems can increase locomotor activity, and daily administration can also sensitize one to the locomotor effect (Kalivas and Duffy 1987). High does of opioids create muscle rigidity and catalepsy. 

Fentanyi (Sublimaze) More potent than morphine. Respiratory depression less likely. Preoperative medication used in anesthesia. Respiratory depression less likely. Muscle rigidity, mild bradycardia. 

Van Der Lee R, Ceelie I, De Wildt SN. Morphine-induced muscle rigidity in a term neonate. Ann Pharmacother 2009 43 1724-6. 

Yuxingcao injection, 772 muscle cramps eplerenone, 344 immunoglobulins, intravenous, 516 phenol, 381 muscle fasdculations suxamethonium, 221 muscle/joint pains naltrexone, 168 muscle rigidity morphine, 160 muscle spasms fenoflbrate, 724 rosuvastatin, 724 simvastatin, 724 muscle vein thrombosis polidocanol, 795 muscle weakness botulinum toxins, 226-7 musculoskeletal pain codeine, 152 cyclobenzaprine, 227 methylnaltrexone, 152 mutagenicity lamivudine, 456 methylphenidate, 5-6... 

Musculoskeletal Muscle rigidity, laryngo-spasm, and respiratory compromise occurred twice in a 2-day-old full-term neonate, first after a bolus dose of morphine 100 micrograms/kg and then after a continuous infusion of 4.4 micrograms/kg/hour [112 ]. 

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