Pediatric Medication Calculations Let’s Practice!

Important Factors when Giving Meds to Children ALWAYS check the ordered drug and dose with a reliable drug resource BEFORE giving Follow the policies and procedures of the facility Most pediatric units require two RN’s to check: The original medication order by the PCP in chart Drug reference for drug and dose for child’s age, weight in kg. and diagnosis The calculations done to determine the correct dose

Calculating the Dose Find Infant/child’s weight in kilograms (kg) PCP may have used admission weight If child’s weight changes during hospitalization, recalculate safe dose and consult with instructor/primary nurse Look up dose recommended for child based on age and weight Calculate the dose Compare to ordered dose and medication sheet With any discrepancies, CHECK before GIVING!

Let’s Practice If you have a calculator/phone, take it out Need child’s weight in kg. If weight listed in pounds, convert to kg. Example: Child weighs 30 pounds 30 /2.2 = 13.6363 kg DON’T ROUND YET - Infant weighs 8 pounds 8/2.2 = 3.6363 kg

Example 1. Calculate the dose of amoxicillin suspension in mLs for otitis media for a 1-yr-old child weighing 22 lb. The dose required is 40 mg/kg/day divided BID and the suspension comes in a concentration of 400 mg/5 mL. Step 1. Convert pounds to kg: 22 lb × 1 kg/2.2 lb = 10 kg Step 2. Calculate the dose in mg: 10 kg × 40 mg/kg/day = 400 mg/day Step 3. Divide the dose by the frequency: 400 mg/day ÷ 2 (BID) = 200 mg/dose BID Step 4. Convert the mg dose to mL: 200 mg/dose ÷ 400 mg/5 mL = 2.5 mL BID Pediatric Dosage Calculations is a sample topic found in Davis's Drug Guide.

Example 2 Calculate the dose of ceftriaxone in mLs for meningitis for a 5-yr-old weighing 18 kg. The dose required is 100 mg/kg/day given IV once daily and the drug comes pre-diluted in a concentration of 40 mg/mL. How many mg. will you give: Daily? ___________________ Each dose?_______________ How many ml. will you give for each dose?________

Here are the Calculations Step 1. Calculate the dose in mg: 18 kg × 100 mg/kg/day = 1800 mg/day Step 2. Divide the dose by the frequency:1800 mg/day ÷ 1 (daily) = 1800 mg/dose Step 3. Convert the mg dose to mL: 1800 mg/dose ÷ 40 mg/mL = 45 mL once daily

Calculating using Ranges Azithromycin (Zithromax) Recommended range for children is 5 mg to 20 mg per kilogram of body weight per day (mg/kg/day), once daily for three to five days. Child weighs 25 lbs. What is the dose range for this child?

Zithromax Calculations 25 lbs/ 2.2 = 11.363636 kg 5 mg to 20 mg per kilogram per day (mg/kg/day) Now Calculate the Range 11.363636 kg X 5 mg = 56.8181 mg 11.363636 kg X 20 mg = 227.2727mg Safe range for this child is 56.82mg to 227.27 mg per day

Safe range for this child is 56.82mg to 227.27 mg per day Med order is Azithromycin 100 mg PO daily Dose 100 mg is within the safe recommended range Safe to give this med and dose

One more problem . . . The recommended daily digoxin dose for treating heart failure in children age 2 to 5 years old is between 10 and 15 mcg per kg of body weight The 3 year old child weighs 32 pounds The order is Digoxin 100 mcg BID PO by elixir The Digoxin elixer has 0.05mg/mL How many ml will you give for each dose?___

Digoxin Calculations Step 1: 32 lbs / 2.2 = 14.545454 kg Step 2: Recommended dose range is 14.5454 X 10 = 145.4545 mcg 14.5454 X 15 = 218.181 mcg 145.45 – 218.18 mcg / day (Round to hundredths here) Step 3: Ordered dose is Digoxin 100 mcg BID PO = 200mcg/day (Dose within range) Step 4: Digoxin elixer has 0.05mg/mL so Convert dose from 100 mcg = 0.1 mg Step 5: Dose 0.1 mg / 0.05mg/mL X 1 = 2 ml Answer is 2 ml each dose. REMEMBER to LABEL!

Practice, Practice . . . Complete the problems on the Pediatric Med Practice forms on Canvas ModulesTab) Answer Key also provided Refer to Kee text Read the problem carefully, follow directions and always label the answers DO WELL on the Med Quiz!