Wyamine

Mephenteramine [Wyamine). This alpha-1 stimulant is used primarily to maintain or restore blood pressure during hypotensive episodes that may occur during spinal anesthesia. It is typically administered by intravenous or intramuscular injection. 

Local anesthetics block the sodium channels, are cardiac depressants, and bring about a ventricular conduction defect and block that may progress to cardiac and ventilatory arrest if toxic doses are given. In addition, these agents produce arteriolar dilation. Circulatory failure may be treated with vasopressors such as ephedrine, metaraminol (Aramine), or mephentermine (Wyamine). Artificial respiration and cardiac massage may also become necessary. Among the local anesthetics, only cocaine blocks the uptake of norepinephrine, causes vasoconstriction, and may precipitate cardiac arrhythmias. 

Wintergreen oil, 763 Wood naphtha, 744 Wood spirit, 744 Woolly foxglove, 700 Wright s Vaporizing Fluid, 450 Wyamine sulfate, 731 Wyamycin E, 589 Wycillin, 926 Wymox, 348... 

Mepben(ermine. N,a,a-Trimethylbenzeneethan-omine N, , trimethylphtnelhylamine 2-methylamino-2--methyl-1 -phenylpropane JV-methyl- -phenyl-lert-butyl. amine Wyamine Vial in Mephine. C H, N mol wt 163,25. C 8092%, H 10.50%. N 8,58%. Prepd by hydrogenating 1 -chloro-2 -methylamino-2-methyl- ]. phenyipropane hydrochloride in methanol in the presence of palladium barium carbonate Bruce, Szabo, U,S, pat. 2,597,445 (1952 to Wyeth). Alternate process Abel et at, US. pat. 2,890,079 (1952 to Wyeth). 

Mephentermine (wyamine sulfate) acts both directly and indirectly. After an intramuscular injection, the onset of action is prompt (within 5—15 minutes), and ejfects may last for several hours. Since the drug releases NE, cardiac contraction is enhanced, and cardiac output and systolic and diastolic pressures usually are increased. The change in heart rate is variable, depending on the degree of vagal tone. Adverse ejfects are related to CNS stimulation, excessive rises in blood pressure, and arrhythmias. Mephentermine is used to prevent hypotension, which frequently accompanies spinal anesthesia. 

Synonyms N-ci,a-Trimethylbenzeneethanamine N-o,o-trimethyl-phenethylamine Trade names Wyamine... 

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