Question

Cephalexin 25 mg/kg/day PO divided q 6h is ordered for a child with a beta-hemolytic streptococcal infection. The child weighs 20 kg. Your bottle of Cephalexin is labeled 125 mg / 5 mL. How many mL will you give the child every 6 hours? .

Answer 1

The child weight is 20 kg

And cephalexin 25 mg per 1 kg body weight in a day p/o divided in q6 h that means 4 times a day

So if 1 kg body weight requires 25 mg cephalexin then

20 kg body weight requires 25×20 mg=500 mg

Now if we divide 500/4 =125 mg  

Because we have to administer total 500 mg cephalexin i every 6 hours means 4 times a day

I have bottle of cephalexin is labelled 125 mg/5 ml

Means 5 ml contains 125 mg of cephalexin

So 5 ml i will give the child every 6 hours