The effect of levodopa on halothane anesthetic requirements.
Acute and chronic levodopa (L-dopa) administration alters halothane minimum alveolar concentration (MAC) in dogs. L-dopa 5, 10, and 25 mg./kg. intravenously (I.V.) reduced halothane MAC 15, 20, and 25 percent, respectively, 1 hour after injection, with return toward normal after 3 hours. Fifty mg./kg. increased halothane MAC 40 percent at 1 hour, but produced at 30 percent decrease from control MAC at 3 hours. Two groups of 4 dogs each given oral L-dopa in doses increasing from 50 mg./kg. daily the 1st week to 300 mg./kg. daily the 5th week, decreased MAC an insignificant 9.5 plus or minus 25.2 percent at 4 hours after the last dose and increased MAC 3.5 plus or minus 7.3 percent at 12 hours after the last dose. A small, insignificant decrease of 9 percent in MAC was measured in 4 dogs given I.V. L-dopa 25 mg./kg. q.i.d for 4 days.
D000284:Administration, Oral; D000769:Anesthesia, Inhalation; D000818:Animals; D004285:Dogs; D006221:Halothane / Q000008:administration & dosage*; D007275:Injections, Intravenous; D007980:Levodopa / Q000008:administration & dosage / Q000494:pharmacology*; D010100:Oxygen; D012119:Respiration; D013997:Time Factors
D007980:Levodopa; D010100:Oxygen; D006221:Halothane