Oral isotretinoin in different dose regimens for acne vulgaris: a randomized comparative trial

Oral isotretinoin is recommended for severe nodulocystic acne in the doses of 1-2 mg/kg/day which is usually associated with higher incidence of adverse effects. To reduce the incidence of side-effects and to make it more cost-effective, the lower dose regimen of isotretinoin has been used.

To compare the efficacy and tolerability of oral isotretinoin in daily, alternate, pulse and low-dose regimens in acne of all types and also to assess whether it can be used for mild and moderate acne also.

One hundred and twenty patients with acne were randomized into four different treatment regimens each consisting of 30 patients. Group A was prescribed isotretinoin 1 mg/kg/day, Group B 1 mg/kg alternate day, Group C 1 mg/kg/day for one week/four weeks and Group D 20 mg every alternate day for 16 weeks. Patients were further followed for eight weeks to see any relapse. Side-effects were also recorded.

Though the daily high dose treatment Group A performed better initially at eight weeks, at the end of therapy at 16 weeks results were comparable in Group A , B and D. Patients with severe acne did better in Group A than in Group B, C and D. Patients with mild acne had almost similar results in all the groups while patients with moderate acne did better in Group A, B and D. Frequency and severity of treatment-related side-effects were significantly higher in treatment Group A as compared to Group B, C and D.

We conclude that for severe acne either conventional high doses of isotretinoin may be used or we can give conventional high dose for initial eight weeks and later maintain on low doses. Use of isotretinoin should be considered in mild to moderate acne also, in low doses; 20 mg, alternate day seems to be an effective and safe treatment option in such cases.