pharmacology math
 
Calculating minimal or maximal dilution
 
spacer .

.

Medication literature indicates that some medications should be mixed or diluted to a specific concentration.  If the literature provides a "range" for dilution, this may be referred to as "minimal dilution" or "maximal dilution".

Example: 

The physician stopped John’s gentamicin and cleocin when the culture report came back.  His new orders include Vancomycin 250 mg IV q 8°.  The literature indicates that the minimal dilution concentration for infusion should be 2.5 mg / ml if given through a peripheral intravenous line (PIV).  How many ml of diluent will the nurse need to mix the Vancomycin to meet this safety requirement? 
Tip:
This will be a division problem.

Calculate: 

250 mg ÷ 2.5 mg = 100 ml of fluid

or

Use this method:

2.5 mg
1 ml
=
250 mg
x ml
2.5 x
=
250
x
=
100
The dosage of Vancomycin should be diluted/mixed in 100 ml of fluid.

Maximal dilution will be calculated by the same method.
..
.
divider bar
show-me page Pediatric Show-Me Index page
10/2003
For questions, contactldp