A patient requires 180 mg ceftriaxone. The l contains 500 mg/5ml of ceftriaxone. You have a 2 ml syringe with l0 divisions per ml. How many divisions in the 2 ml syringe will you fill to give 180 mg ceftriaxone?
(A) 9 (B) 18 (C) l0 (D) 12
(B) Ans: B. 18500 mg/ 5 ml means 100 mg/l ml. Since 100 mg is present in 1 ml, therefore, 180 mg of drug is present in 1.8 ml.Now it is clear that we must administer 1.8 ml of the above solution to administer the desired amount of drug.Last thing is to calculate the divisions to administer 1.8 ml.10 division per ml means each 0. 1 ml is equal to 1 division.Therefore, 1 .8 ml will be equal to l8 divisions.