Question

The medication ordered for your patient has a strength (concentration) of 0.2g in 2 mL. Prepare a dose of 250mg. How many mL will you administer?

Answer 1

According to the question,

Concentration of the medication = 0.2 g in 2 mL.

= 0.2 x 1000 mg in 2 mL

= 200 mg in 2 mL.

Now, we need to prepare a dose of 250 mg. This can be done by the "Desired Over Have" OR Formula method.

According to this method, the formula for calculating an unknown quantity of drug is:

A = D/H x V

where, A = Amount of medication to be given to the patient

D = Desired dose to be given = 250 mg

H = Dose already at hand = 200 mg

V = Vehicle in which medication is delivered = 2 mL (here it is delivered in a liquid of certain quantity).

Therefore, now, Amount of medication to be administered = 250 mg/200 mg x 2 mL

= 5/4 x 2 mL

= 2.5 mL.

Thus, to deliver the required dose of 250 mg, 2.5 mL of medication must be administered to the patient.