Hair Loss From Isotretinoin: How common is hair loss and do higher doses increase the chance?

New Study Identified Hair Loss in 3.2% to 5. 7% of Users

Isotretinoin is a commonly used oral medication for the treatment of acne. Over 1 million isotretinoin prescriptions are authorized in the United States per year. A variety of side effects can occur and hair loss is among the ones that patients are frequently particularly worried about. Telogen effluvium or hair shedding is one of the types of hair loss that isotretinoin is known to cause in a small proportion of users. Hair loss occurs at variable times after starting istoretinoin. In one study by Demirseren et al, the authors showed that 20% of 300 patients experienced hair loss, with a median time of onset at 4 weeks and a wide range of 1 to 24 weeks,

Lytvyn et al, 2022

In a new study by Lytvyn and colleagues, the authors set out to evaluate the frequency of hair loss in patients with acne vulgaris treated with less than 0.5 mg/kg/d daily doses of isotretinoin versus the frequency of hair loss in patients with acne vulgaris treated with dosing greater than 0.5 mg/kg/d daily. A systematic review was performed in studies that involved the use of isotretinoin for acne and described hair loss outcomes and were of an observational or experimental design. Twenty-two studies were identified that reported hair loss outcomes with oral isotretinoin treatment for acne. 16 were prospective trials, 3 were retrospective studies, and 3 were cross- sectional studies

Results

A total of 565 acne patients were treated with doses less than 0.5 mg/kg/d of isotretinoin (mean age, 22.0 years; men, 63.7%). Hair loss was reported in 18 (3.2%) of all patients treated with less than 0.5-mg/kg/ day dosing. A total of 3375 acne patients were treated with doses greater than 0.5 mg/kg/d of isotretinoin (mean age, 22.4 years; men, 60.7%). Hair loss was reported in 192 (5.7%) of all patients treated with greater than 0.5-mg/kg/ day dosing.

Conclusion

About 1 in 20 patients who use isotretinoin experience hair loss. The risk is dose dependent - with patients using doses about 0.5 mg per kg have a nearly two fold higher chance of hair loss than those using less than 0.5 mg per kg.

REFERENCE

Demirseren et al. The weeks and the cumulative doses of the first adverse events related to oral isotretinoin in acne patients: analysis of 300 patientsJ Dermatolog Treat. 2017 Jun;28(4):309-313.

Lytvyn et al. Comparing the frequency of isotretinoin-induced hair loss at <0.5-mg/kg/d versus ≥0.5-mg/kg/d dosing in acne patients: A systematic review. JAAD Int. 2022 Mar; 6: 125–142.