The Requirement to Monitor Low-dose Oral Minoxidil in the Management of Hair Loss

Low-dose oral minoxidil (LDOM) can safely and effectively treat numerous hair disorders. Reported doses range from 0.25 mg to 5 mg daily titrated against clinical effectiveness and adverse events. Some clinicians advocate routine monitoring of patients treated with LDOM. However, there is limited evidence on whether minoxidil in such small doses adversely impacts patients with normal hemodynamic and biochemical baseline profiles.

The aim of the study is to evaluate the need for regular monitoring of patients treated with LDOM.

This is a retrospective analysis of patients treated with LDOM in a tertiary hair clinic between April 2017 and June 2020. The clinical and laboratory parameters were assessed every 6 months. On commencing LDOM, baseline blood pressure, heart rate, and weight were recorded, and renal and liver function tests were performed.

The data were analyzed using graphical exploration.

The heart rate, weight, renal function, and liver function appeared stable throughout the treatment course. The weight and estimated glomerular filtration rate showed a trend to increase over time, but these findings were not statistically significant for any of the outcomes.

The data support the position that routine monitoring is not required during treatment in asymptomatic patients with normal baseline values. Regular monitoring of blood pressure, heart rate, weight as well as liver and kidney function is not required during treatment with LDOM in patients with normal hemodynamic and biochemical baseline profiles. Patients with preexisting renal impairment can be prescribed oral minoxidil; however, we advocate ongoing monitoring in this subgroup, especially those with moderate-to-advanced disease. To the best of our knowledge, this is the first study that provides longitudinal monitoring data for LDOM with a follow-up period beyond 6 months and up to 36 months on treatment.