Isotretinoin (Accutane) Dosage Calculator
Calculate isotretinoin dosage by weight with daily dose, BID individual dose, capsule suggestions, and cumulative dose tracking. Free Accutane dose calculator for acne treatment planning.
About This Calculator
The Isotretinoin (Accutane) Dosage Calculator helps patients and healthcare providers determine appropriate isotretinoin dosing for the treatment of severe recalcitrant nodular acne. By entering body weight, prescribed daily dose per kilogram, and planned treatment duration, the calculator provides the total daily dose, individual twice-daily (BID) dose, suggested capsule combinations, total cumulative dose, and progress toward the standard target cumulative dose of 120–150 mg/kg.
Isotretinoin is a retinoid (vitamin A derivative) that works by reducing sebum production, normalizing follicular keratinization, and decreasing inflammation. Standard dosing begins at 0.5 mg/kg/day divided into two doses, with potential escalation to 1.0 mg/kg/day based on tolerance and severity. The typical treatment course lasts 16–20 weeks, and clinical studies demonstrate that achieving a cumulative dose of 120–150 mg/kg is associated with optimal long-term remission rates. Available capsule strengths include 10 mg, 20 mg, 30 mg, and 40 mg, and the calculator suggests appropriate combinations to match your prescribed individual dose.
Important Safety Information
Isotretinoin has significant teratogenic effects and must not be used during pregnancy. In the United States, isotretinoin is available only through the iPLEDGE Risk Evaluation and Mitigation Strategy (REMS) program, which requires enrollment of prescribers, patients, pharmacies, and distributors. Female patients of reproductive potential must use two forms of contraception and undergo regular pregnancy testing. Regular monitoring of liver function tests and fasting lipid profiles is required throughout treatment. Common side effects include dry skin, cheilitis (chapped lips), dry eyes, and joint pain. Patients should be monitored for mood changes and instructed to report any signs of depression or suicidal ideation immediately.
Frequently Asked Questions
How is isotretinoin dosage calculated?
Isotretinoin dosage is calculated based on body weight, typically starting at 0.5 mg/kg/day divided into two doses (BID). The dose may be increased to 1.0 mg/kg/day based on tolerance and response. The total daily dose equals your weight in kg multiplied by the prescribed mg/kg/day.
What is the target cumulative dose for isotretinoin?
The standard target cumulative dose for isotretinoin is 120–150 mg/kg total over the entire treatment course. This target is based on clinical studies showing optimal long-term remission rates for severe nodular acne at this cumulative range.
How long does isotretinoin treatment typically last?
A typical isotretinoin treatment course lasts 16–20 weeks (4–5 months). Some patients may require longer treatment depending on their response, tolerance, and cumulative dose target. The maximum recommended treatment duration is typically 20 weeks per course.
What capsule strengths are available for isotretinoin?
Isotretinoin is available in capsule strengths of 10 mg, 20 mg, 30 mg, and 40 mg. The calculator suggests which combination of capsules to take for each individual dose based on your prescribed amount. Capsules should be swallowed whole with a full glass of liquid.
Is this calculator free to use?
Yes, this isotretinoin dosage calculator is completely free to use with no registration required. It helps patients and healthcare providers estimate appropriate dosing based on weight and treatment goals.
Do I need monitoring while taking isotretinoin?
Yes, isotretinoin requires regular monitoring including pregnancy tests for females of reproductive potential, liver function tests at baseline and periodically, and fasting lipid and blood glucose levels. Patients must be enrolled in the iPLEDGE REMS program in the United States.
What is the iPLEDGE program?
iPLEDGE is a Risk Evaluation and Mitigation Strategy (REMS) program required by the FDA for all isotretinoin prescriptions in the United States. It aims to prevent fetal exposure to isotretinoin, which causes severe birth defects. Prescribers, patients, pharmacies, and distributors must all be enrolled in the program.
Can isotretinoin be taken once daily?
Isotretinoin is typically dosed twice daily (BID) at 0.25 to 0.5 mg/kg per dose. The safety and efficacy of once-daily dosing has not been established, so twice-daily administration is recommended. Capsules should be taken with food for optimal absorption.