Vistaril 75 mg IM is ordered for anxiety. Available: 50 mg/mL. How many milliliters will the nurse administer?

Choice A reason: 1 mL gives 50 mg; this underdoses the 75 mg order, reducing Vistaril’s sedative effect, risking inadequate anxiety relief for the patient. Choice B reason: 1.5 mL is correct; 75 mg divided by 50 mg/mL equals 1.5 mL, delivering the precise IM dose for effective anxiolytic action safely. Choice C reason: 2 mL provides 100 mg; this overdoses Vistaril, risking excessive sedation or hypotension, exceeding the ordered therapeutic amount unnecessarily. Choice D reason: 2.5 mL yields 125 mg; this far exceeds 75 mg, amplifying side effects like drowsiness or respiratory depression, unsafe for anxiety management.