July 14, 2024
Here's How to Calculate the Correct Dosage of Medicine, Let's Check It Out!

Understanding how to calculate medication doses correctly is very important to maintain health and safety when taking medication. Mistakes in calculating drug doses can be fatal, therefore it is important to understand the correct steps in calculating the required drug dose.

1. Know the drug data

The first step in calculating drug dosage is to know the data of the drug to be used. Information that needs to be known includes the name of the drug, the strength of the drug (dose per unit), how to use it, and the frequency of use.

2. Determine the dose needed

After knowing the drug data, the next step is to determine the required dose. Drug doses can be categorized into single doses and daily doses. A single dose is a dose of medication given only once, while a daily dose is the total dose of medication given in one day.

3. Calculating the drug dose

After determining the required dose, the next step is to calculate the drug dose based on the available drug strength. There are several formulas that can be used to calculate drug doses, including:

  • Rumus Dosage on Hand: Dose given = (Requirement × Weight) / Strength
  • Rumus Dimensional Analysis: Dose given = (Requirement × Weight) / (Power × Unit)
  • Rumus Ratio and Proportion: Dose given = (Requirement × Weight) / (Strength)

4. Example of calculating drug dosage

For example, if someone needs a paracetamol dose of 500 mg, while one paracetamol tablet has a strength of 250 mg, then how many paracetamol tablets should be consumed?

Using the Dosage on Hand formula, we can calculate:

The dose given = (500 mg × 1 tablet) / 250 mg = 2 tablets

So, a person must take 2 paracetamol tablets to reach a dose of 500 mg.

5. Pay attention to side effects and drug interactions

In addition to calculating the drug dose correctly, it is also important to pay attention to possible side effects and drug interactions. Some drugs can cause side effects if taken in the wrong dosage or if they interact with other drugs being used. Consult a doctor or pharmacist if you have concerns regarding side effects or drug interactions.

6. Conclusion

Calculating medication doses correctly is essential to ensure safe and effective medication use. By understanding the correct steps in calculating drug doses, we can avoid the risk of overdosing or underdosing which can endanger health. Don't hesitate to consult a doctor or pharmacist if you have difficulty calculating the correct dosage of medication.


1. Basic Pharmacology Book

2. Journal of Modern Medicine

3. Professional Pharmacist Knowledge