Question

v. Dosage Calculation by Body Surface Area 20. Mustargen 6 mg/m² as a single IV dose. BSA = 1.5 m² How many ml should be administered per dose if eh stock 10 mg/ml? 21. Cyclophosphamide 100 mg/m²/day p.o. What is the dose per day if the client weighs 160 lbs and is 5 ft and 10 in. tall? 22. Sulfisoxazole 2 g/ m / day in four divided doses. Child's height is 50 in, and weighs 60 lbs. a) What is the dose per day? b) How many ml of the drug should be administered per dose of the stock is 500 mg/5 ml? 23. Methotrexate 50 mg/m²/weekly. Height = 54 Weight = 90 lbs. Drug dosage: 25-75 mg/m²/weekly. a) What is the weekly dose? b) Is it within the recommended range?

Answer 1

Answer 20. Mustergen dose= 6mg/m² BSA=1.5m²

So total  dose required= 6x1.5= 9 mg

s Given the stock contains 10mg / ml

that means 10 mg present in 1 ml solution

so we can write 1mg present in 1/10ml solution

Hence 9mg present in 9x1/10ml=0.9ml

So 0,9ml to be given

Answer No 21.

There are two formulae for calculation of Doses by Body surface area

e.g

1.BSA Dubois[m2] = 0.007184*height(cm)^0.725  *weight(Kg)^0.425

2.BSA Mosteller[m2] = sqr(Height[cm] * Weight[kg] / 3600)

following BSA Dubois

BSA based dose= ( considering the given values e.g dose=100 mg/ meter ² /day and converting Height into cm it comes to 177 cm and weight in Kg converted to lb to fit into the formula of Dubois weight =160lb ) it comes to =189.23mg

Answer 22

Sulfifoxazole dose per day BSA based=

2gm=2000mg/meter²  /day

Height =50inches= 127cm

Weight = 60 lb=27.21 kg

Answer a)is 1960.88mg =Dose per day (to be divided in four shots)

Total =1960

divided by 4 =490mg

b) the stock contains .......

500mg is present in 5ml

1mg is present in 5/500ml=1/100=0.01ml

490mg is present in 490*0.01=4.9ml which should be the amount

Answer 23. =61.583=62 mg/week (Rounded off)

Here the conversion is done as before and the values are put into the formulae of DUbois and it is with ih the limit.

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