naplex calculations

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kt44

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can some body help me in solving these calculations.
1- 90ml of distilled water is usually added to constitute a cefaclor powder of 150ml size to yield 250mg/ml. The normal dose for therapy in children with this antibiotic is 20mg/kg/day. Th e cefaclor was mistakenly prepared with 100ml. what volume of solution will deliver 250mg?

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90 ml of water = 150 ml of Cefaclor 250mg/5 ml
150ml (total volume) - 90ml (amount of water added) = 60 ml (powder volume)

In 5 ml there are 250 mg, so in 150 ml there will be: 250mg/5ml = X mg/ 150 ml
= 37500 mg

Since 100 ml were added instead of 90 ml, and we know the powder volume is 60 ml, the total volume of Cefaclor is 160 ml.
The amount of drug is the same - 37500 mg.

Now set up the ratio to find how many mls of the new concentration is equal to 250 mg.

37500 mg/160 ml = 250 mg/Xml

= 1.0666

The normal dose of 20mg/kg/day is just there to confuse you.

Hope this helps!
 
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90 ml of water = 150 ml of Cefaclor 250mg/5 ml
150ml (total volume) - 90ml (amount of water added) = 60 ml (powder volume)

In 5 ml there are 250 mg, so in 150 ml there will be: 250mg/5ml = X mg/ 150 ml
= 37500 mg

Since 100 ml were added instead of 90 ml, and we know the powder volume is 60 ml, the total volume of Cefaclor is 160 ml.
The amount of drug is the same - 37500 mg.

Now set up the ratio to find how many mls of the new concentration is equal to 250 mg.

37500 mg/160 ml = 250 mg/Xml

= 1.0666

The normal dose of 20mg/kg/day is just there to confuse you.

Hope this helps!
What strength will albuterol 0.5% endup based on drug order to mix it with 2.5ml NS .? Kindlly help me solve this calculation correct answr is 0.083%
 
Ummm doesn't albuterol solution come in 0.083%. i don't know whats the confusion and your question is clearly.
 
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