Question

Calculate the dosages to be given. Use labels where provided. Order: Retrovir \(80 \mathrm{mg}\) p.o. \(\mathrm{q} 8 \mathrm{~h}\). Available: Retrovir syrup labeled \(50 \mathrm{mg}\) per \(5 \mathrm{~mL}\)

Short answer

Administer 8 mL of Retrovir syrup per dose.

Step-by-step solution

Understand the Medication Order

The order requires that a patient receives Retrovir dosage of 80 mg orally every 8 hours. This means we need to calculate the dosage to be given per dose to achieve this.

Check the Concentration of the Available Medication

The available Retrovir syrup is labeled with a concentration of 50 mg per 5 mL. This means for every 5 mL of syrup you have 50 mg of Retrovir.

Use Proportion to Calculate Needed Volume

To calculate how many milliliters contain 80 mg of Retrovir, we set up a proportion based on the concentration: \( \frac{50 \text{ mg}}{5 \text{ mL}} = \frac{80 \text{ mg}}{x \text{ mL}} \) where \( x \) is the volume in mL needed for 80 mg.

Solve the Equation

Cross-multiply to solve the proportion: \( 50 \cdot x = 80 \cdot 5 \). This simplifies to \( 50x = 400 \). Divide both sides by 50 to solve for \( x \). \( x = \frac{400}{50} = 8 \).

Interpret and Verify the Solution

The solution tells us that to deliver an 80 mg dose of Retrovir, you need to administer 8 mL of the syrup. This is consistent with the concentration provided.

Key concepts

Using the Proportion Method for Medication Dosage

When calculating medication dosages, the proportion method is a reliable tool. It lets you find the correct amount of liquid medication needed based on its concentration. In our context, Retrovir syrup has a known concentration of 50 mg per 5 mL. To calculate how much syrup is needed for a dose of 80 mg, use the proportion formula:

• Determine known values: 50 mg is to 5 mL.
• Set up the proportion: \( \frac{50 \text{ mg}}{5 \text{ mL}} = \frac{80 \text{ mg}}{x \text{ mL}} \)
• Solve for unknown \( x \): Cross-multiply to find \( 50 \cdot x = 80 \cdot 5 \).

This simple equation can be solved step-by-step to find that \( x = 8 \text{ mL} \). Cross-multiplying ensures you're processing the calculation correctly, allowing you to scale the original concentration to meet the prescribed dosage. It's a vital skill in both understanding and executing medication administration safely.

Understanding Medication Concentration

Medication concentration is crucial for calculating the right dosage. It tells you how much active ingredient is contained in a specified volume of liquid. For Retrovir syrup, the concentration is labeled as 50 mg per 5 mL. This means each 5 mL of syrup contains 50 mg of the active medication. Knowing the concentration allows healthcare professionals to calculate the exact amount of liquid needed for any prescribed dose. If a dose requires 80 mg, you'll need a specific amount of syrup. This calculation helps avoid errors, ensuring patients receive the correct dosage, which is essential for the medication to be effective.

• Check the concentration label carefully.
• Use the concentration to set up dosage calculations.

Always understand the concentration before attempting to calculate doses. It is your stepping stone to accuracy in medication management.

Key Steps in Oral Medication Administration

Administering oral medication involves specific steps to ensure safety and effectiveness. With Retrovir syrup, dosing must be precise to administer the correct amount every 8 hours. The process begins with understanding the medication order and calculating the dose using syrup's concentration. Once calculation confirms the needed volume – 8 mL for 80 mg – ensure that this precise amount is measured using an oral syringe or medicine cup, which are tools designed to provide accurate dosing.

• Read the prescriptions and instructions thoroughly.
• Double-check calculated doses.
• Use tools like syringes or cups for accuracy.
• Monitor the patient for any adverse reactions post-administration.

Administering oral medications carefully ensures treatment success and reduces the risk of errors. These steps guide you through the intricate process, from calculation to administration, ensuring the right dose is given at the right time.