A child requires Cephalexin (Keflex) 100 mg suspension qid. If the label states 125 mg in 5 ml, how many ml should the nurse administer per dose?

To determine the correct dosage in milliliters for the child, you start by calculating how many milliliters contain the required 100 mg of Cephalexin based on the concentration provided. The label indicates that there are 125 mg in 5 ml.

First, it's important to establish the amount of medication per milliliter. If you have 125 mg in 5 ml, then to find out how many milligrams are in 1 ml, you divide 125 mg by 5 ml, resulting in 25 mg/ml.

Next, you need to find out how many milliliters will provide the necessary 100 mg dose. To find this, you can set up a simple calculation:

1. Determine the volume needed for 100 mg using the concentration:

[

\text{Volume} = \frac{\text{Desired Dose (mg)}}{\text{Concentration (mg/ml)}}

]

[

\text{Volume} = \frac{100 \text{ mg}}{25 \text{ mg/ml}} = 4 \text{ ml}

]

Thus, to achieve the required dosage of 100 mg, the nurse should administer 4 ml of the