Isotretinoin Cumulative Dose Calculator

The Isotretinoin Cumulative Dose Calculator estimates the total milligrams taken over time based on weight, daily dosage, and treatment length. This tool helps patients and doctors track treatment progress to ensure a full course for lasting acne clearance. Whether you are starting therapy, checking your current levels, or planning the end of treatment, this tool ensures you stay on track.

Enter the patient's weight in kilograms
Enter the prescribed daily dose in milligrams
Enter the planned or current treatment duration in months
Enter the cumulative dose already taken (0 if just starting)
Select the target cumulative dose based on treatment goals

How Cumulative Dose Is Calculated

Cumulative dose represents the total amount of medication absorbed by your body throughout the entire treatment course. It is essential because reaching a specific total amount per kilogram of body weight is proven to reduce the chance of acne returning.

Total Cumulative Dose = (Daily Dose × 30 × Duration) + Current Dose

Where:

  • Daily Dose = Milligrams taken per day
  • Duration = Length of treatment in months
  • Current Dose = Total milligrams already taken

The calculation assumes an average of 30 days per month to convert your daily intake into a total sum. Finally, dividing this total by your weight provides the precise mg/kg ratio needed to assess effectiveness.

What Your Cumulative Dose Means

This number tells you how close you are to the specific goal required for long-term remission. It is not just about how many pills you take, but how that total relates to your specific body size.

Preventing Relapse: Most medical guidelines suggest reaching a target between 120 and 150 mg/kg to significantly lower the risk of acne returning. If your result is below 100 mg/kg, you may be at a higher risk for relapse.

Severe Cases: For very stubborn or severe acne, doctors often aim for a higher target, sometimes up to 220 mg/kg. This ensures the oil glands are fully suppressed.

Treatment Planning: If your result shows you are behind schedule, your doctor might increase your daily dose or extend the treatment by a few months.

This calculator is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

Use this tool at every check-up to discuss your progress and decide if any changes are needed to reach your target safely.

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