Drug calculation formula Strength required volume of stock Strength of hand X 1 = volume required How many 50 mg tabs should be given for a dose of 75mg? 75 x 1 3 50 1 = 2 = 1 1/2

200 Ordered: 15mg. Stock on hand 30mg. How many tablets? 15 x 1 = 1 Ordered 300mg. Stock is 200mg in one tab. How many tabs? 300 x 1 = 1 1/2 200

Steps: Convert 0.25mg to mcg 1mg = 1000mcg 0.25 mg = 250mcg Patient is ordered 0.25mg of digoxin. The digoxin available is in tabs containing 125mcg. How many tabs should the patient receive? Steps: Convert 0.25mg to mcg 1mg = 1000mcg 0.25 mg = 250mcg then apply formula: 250/ 125 x 1 tab = 2 tabs

A patient is ordered 150mg of aspirin. On hand are tablets of 300mg A patient is ordered 150mg of aspirin. On hand are tablets of 300mg.How many tablets do I give? 150/300 x 1/1 = ½ tab. The stock on hand of diazepam is 5 mg. How many tablets are to be administered if the order is for 12.5mg? 12.5/5 x 1/1 = 125/50 x 1/1 = 5/2 x 1/1 = 2.5 tabs

A syrup contains penicillin 125mg/5ml A syrup contains penicillin 125mg/5ml. How much syrup do I administer for 250mg? 250/125 x 5/1 = 2/1 x 5/1 = 10/1 = 10 ml 480mg of Paracetamol is prescribed. The stock solution is 120mg in 5ml. How many ml do I administer? 480/120 x 5/1 = 4/1 x 5/1 = 20/1 = 20 ml