Question

1. The order for Cephalexin 500 mg PO every 12 hours is written by the MD. The pharmacy sends a bottle with the label reading Cephalexin 250 mg/10mL. How many tsp will need to be given with this AM dose?

Answer 1

ANSWER.

* Calculation of tsp of drug required.

          Formula = Desired dose/Dose in hand * Quantity.

     Here

          Desired dose(D) = 500 mg.

          Dose in hand (H) = 250 mg.

               Quantity(Q) = 10 ml

As per above formula

       Volume(ml) of drug required = D/H * Q

                                                     = 500/250 * 10

                                                     = 2 * 10

                                                     = 20 ml.

                               1 tsp = 5 ml.

        So

          tsp(Teaspoon) of drug required = 20/5

                                                                   = 4 tsp.