Isotretinoin mg/kg daily doses and cumulative course totals for the GPhC assessment

The manufacturer's UK product information for isotretinoin 10 mg soft capsules states that therapy should be started at a dose of 0.5 mg/kg daily, and that for most patients the dose ranges from 0.5 to 1.0 mg/kg per day.

The same information states that long-term remission and relapse rates are more closely related to the total dose administered than to either duration of treatment or daily dose, that no substantial additional benefit is to be expected beyond a cumulative treatment dose of 120 to 150 mg/kg, and that a treatment course of 16 to 24 weeks is normally sufficient to achieve remission.

It also states that isotretinoin should only be prescribed by or under the supervision of physicians with expertise in the use of systemic retinoids for the treatment of severe acne, and that in patients with severe renal insufficiency treatment should be started at a lower dose, for example 10 mg/day.

Each question fixes the values needed for its arithmetic. Write the unit beside every step and distinguish a daily dose from a cumulative course total. All prescriptions and patients here are fictional; these are revision materials, not for patient care.