A nurse is preparing to administer diphenhydramine 40mg IM to a client who has allergies. Available is diphenhydramine injection 50mg/mL. How many mL should the nurse administer? Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero

Given: Prescribed dose: 40 mg of diphenhydramine Available concentration: 50 mg/mL Steps to solve: Determine the volume to be administered: Set up a proportion to solve for the unknown volume (X): 50 mg/mL = 40 mg/X mL Cross-multiplying gives us: 50 mg x X mL = 40 mg x 1 mL Simplifying: 50X = 40 Solving for X: X = 40 / 50 = 0.8 mL