Question

Calculate the dosages below. Use the labels where provided. Calculate to the nearest hundredth where necessary. Order: Atropine \(0.1 \mathrm{mg}\) subcut stat. Available: Atropine \(400 \mathrm{mcg}\) per mL

Short answer

Administer 0.25 mL of Atropine.

Step-by-step solution

Convert the ordered dose

First, we convert the ordered dose from milligrams (mg) to micrograms (mcg). Since 1 mg equals 1000 mcg, we can convert 0.1 mg to mcg by multiplying: \[0.1 \text{ mg} = 0.1 \times 1000 = 100 \text{ mcg}\]

Determine the volume to administer

Next, we use the concentration formula to find out how much volume is needed. The available concentration is 400 mcg/mL. We need to find the volume for 100 mcg.Using the proportion \( \frac{400 \text{ mcg}}{1 \text{ mL}} = \frac{100 \text{ mcg}}{x \text{ mL}} \), solve for \( x \) by cross-multiplying:\[400x = 100 \times 1\]\[400x = 100\]\[x = \frac{100}{400} = 0.25\text{ mL}\]

Conclusion

The volume of Atropine to be administered is \(0.25\text{ mL}\). Make sure to round according to the nearest hundredth as required, which in this case results in the value already being at the nearest hundredth.

Key concepts

Unit Conversion

Understanding how to convert between different units is crucial in dosage calculations as medications are often dispensed in a variety of units. Converting between milligrams and micrograms is a common necessity in pharmacology. For example, if a medication needs to be converted from milligrams (mg) to micrograms (mcg), you should remember that:

• 1 mg = 1000 mcg

So, to convert 0.1 mg to mcg, multiply 0.1 by 1000 to get 100 mcg. Always keep a calculator handy to ensure accuracy in these conversions. Accurate conversions are critical not only for safe dosing but also because they ensure you are working with the correct measurements.
Consistency in units helps prevent errors that could arise if incorrect unit conversion goes unnoticed.

Medication Dosing

Calculating the correct dosage of medication is vital for patient safety and treatment efficacy. The ordered dose must typically be matched to the form in which the medication is supplied. Start by comparing the prescribed dose with the available dose. If they are in different units, a conversion may be needed. After this, you'll need to calculate how much of the available medication is needed to meet the ordered dose.

• For example, if ordered is 0.1 mg and available is 400 mcg/mL, first convert 0.1 mg to 100 mcg.

This lays a solid foundation for subsequent calculations. Always cross-check your calculations as a part of safe practice in medication dosing.

Volume Calculation

When prescribing medications, it's often required to determine the volume of liquid medication required for a certain dose. This involves using the concentration of the available medication.Imagine the available medication is in a solution of some concentration, say 400 mcg/mL. You have already calculated the necessary dose in mcg; the next step is to calculate the volume to be administered:

• Set up a proportion: \( \frac{400 \text{ mcg}}{1 \text{ mL}} = \frac{100 \text{ mcg}}{x \text{ mL}} \)
• Cross-multiply to solve for \(x\), which yields \( x = 0.25 \text{ mL} \).

Volume calculation is a straightforward process, but attention to detail is crucial to avoid dosing errors.

Pharmacology

Pharmacology is the science of drug action and its effects on the body. It includes understanding how medications work, their side effects, and how they interact with each other. A critical aspect of pharmacology involves calculating correct dosages and understanding the implications of dosing errors. Mistakes in dosages can lead to ineffective treatment or adverse drug reactions.

• Always adhere to guidelines for dosage calculations.
• Stay informed about medication updates and evidence-based practices.

Being well-versed in pharmacology helps healthcare professionals make informed decisions about medication administration and manage drug therapies effectively.