Occasionally, an idiosyncratic reaction may follow the first dose of a skeletal muscle relaxant. Symptoms, seen within minutes or hours of the first dose, include:
a. severe nausea, vomiting, and weakness.
b. temporary loss of vision, weakness, dizziness, and confusion.
c. respiratory depression, confusion, and drowsiness.
d. paradoxical excitation, insomnia, and tachycardia.