Safety of low-dose oral minoxidil for hair loss: A multicenter study of 1404 patients

Background The major concern regarding the use of low-dose oral minoxidil (LDOM) for the treatment of hair loss is the potential risk of systemic adverse effects. Objective To describe the safety of LDOM for the treatment of hair loss in a large cohort of patients. Methods Retrospective multicenter study of patients treated with LDOM for at least 3 months for any type of alopecia. Results A total of 1404 patients (943 women [67.2%] and 461 men [32.8%]) with a mean age of 43 years (range 8-86) were included. The dose of LDOM was titrated in 1065 patients, allowing the analysis of 2469 different cases. The most frequent adverse effect was hypertrichosis (15.1%), which led to treatment withdrawal in 14 patients (0.5%). Systemic adverse effects included lightheadedness (1.7%), fluid retention (1.3%), tachycardia (0.9%), headache (0.4%), periorbital edema (0.3%), and insomnia (0.2%), leading to drug discontinuation in 29 patients (1.2%). No life-threatening adverse effects were observed. Limitations Retrospective design and lack of a control group. Conclusion LDOM has a good safety profile as a treatment for hair loss. Systemic adverse effects were infrequent and only 1.7% of patients discontinued treatment owing to adverse effects. The major concern regarding the use of low-dose oral minoxidil (LDOM) for the treatment of hair loss is the potential risk of systemic adverse effects. To describe the safety of LDOM for the treatment of hair loss in a large cohort of patients. Retrospective multicenter study of patients treated with LDOM for at least 3 months for any type of alopecia. A total of 1404 patients (943 women [67.2%] and 461 men [32.8%]) with a mean age of 43 years (range 8-86) were included. The dose of LDOM was titrated in 1065 patients, allowing the analysis of 2469 different cases. The most frequent adverse effect was hypertrichosis (15.1%), which led to treatment withdrawal in 14 patients (0.5%). Systemic adverse effects included lightheadedness (1.7%), fluid retention (1.3%), tachycardia (0.9%), headache (0.4%), periorbital edema (0.3%), and insomnia (0.2%), leading to drug discontinuation in 29 patients (1.2%). No life-threatening adverse effects were observed. Retrospective design and lack of a control group. LDOM has a good safety profile as a treatment for hair loss. Systemic adverse effects were infrequent and only 1.7% of patients discontinued treatment owing to adverse effects.