LDOM has a high compliance to treatment and a low cost but, as every medication, it has several contraindications and precautions. LDOM carries a black box warning due to the risk of pericardial effusion and angina pectoris exacerbation, particularly in severe hypertension and cardiovascular event-prone individuals. It has minimal hypotensive effects in normotensive patients. Contraindications include pheochromocytoma, hypersensitivity reactions, and pregnancy (due to neonatal hypertrichosis risk). It's also contraindicated in nursing mothers. LDOM is generally well tolerated, with hypertrichosis (excessive hair growth) being the most common side effect. Temporary hair shedding is a less common side effect, primarily associated with topical minoxidil. Other side effects at low doses include postural hypotension, lower limb edema, headaches, mild blood pressure changes, and EKG alterations, which are generally mild.
(Patel, P., Nessel, T. A., & Kumar D, D. (2023). Minoxidil. In StatPearls. StatPearls Publishing.). https://pubmed.ncbi.nlm.nih.gov/29494000 ; (Cauhe, J. J., Pirmez, R., Ramos, P. M., Melo, D. F., Quijano, D. O., Moreno-Arrones, O. M., Corralo, D. S., Redondo, R. G., Gelbard, A. H., Sanabria, B. D., Restom, D., Porriño-Bustamante, M. L., Ortega, C. P., Rico, E. B., Nieto, D. F., Ramos, M., Olasolo, P. J., & Galvan, S. V. (2023). Safety of low-dose oral minoxidil in patients with hypertension and arrhythmia: a multicenter study of 264 patients. Seguridad de minoxidil oral a dosis bajas en pacientes con hipertensión o arritmias: estudio multicéntrico de 264 pacientes. Actas dermo-sifiliograficas, S0001-7310(23)00679-8. Advance online publication. https://doi.org/10.1016/j.ad.2023.07.019). https://pubmed.ncbi.nlm.nih.gov/37652097/
Low dose OM in AGA is indicated in those patients who are poorly compliant to the topical solution due to undesirable hair texture, scalp irritation or allergic reaction to minoxidil or excipients, or unwilling to apply the medication twice a day. It can also be associate to topical or systemic finasteride to promote further hair regrowth, as they have a different mechanism of action.
Ramírez-Marín HA, Tosti A. Role of Oral Minoxidil in Patterned Hair Loss. Indian Dermatol Online J. 2022 Oct 12;13(6):729-733. doi: 10.4103/idoj.idoj_246_22. PMID: 36386734; PMCID: PMC9650732.) https://pubmed.ncbi.nlm.nih.gov/36386734/
Topical Finasteride
Topical finasteride (TF) is a novel medication used for the treatment of androgenetic alopecia. It is designed to address the therapeutic challenge posed by AGA. TF works by inhibiting the enzyme 5-alpha-reductase, which blocks the conversion of testosterone to dihydrotestosterone (DHT). Unlike oral finasteride, TF primarily acts locally in the hair follicles, minimizing systemic effects.
Studies have shown that TF can effectively lower scalp DHT levels, leading to hair regrowth (Figure 2). Clinical trials have demonstrated that TF increases hair count in patients with AGA, with results at 6 months similar to those obtained by oral finasteride, while it has minimal effects on plasma DHT levels, thereby reducing adverse effects. The most common adverse effects associated with TF are skin irritation and itching at the application site.
(Kaiser, M., Abdin, R., Gaumond, S. I., Issa, N. T., & Jimenez, J. J. (2023). Treatment of Androgenetic Alopecia: Current Guidance and Unmet Needs. Clinical, cosmetic and investigational dermatology, 16, 1387–1406. https://doi.org/10.2147/CCID.S385861) https://pubmed.ncbi.nlm.nih.gov/37284568/
TF is typically available as a 0.25% finasteride spray applied once daily to the scalp. Some studies have explored the combination of topical minoxidil and TF to enhance the efficacy. This combination has shown promising results in increasing hair density and diameter while maintaining relatively stable serum DHT concentrations.
(Devjani S, Ezemma O, Kelley KJ, Stratton E, Senna M. Androgenetic Alopecia: Therapy Update. Drugs. 2023 Jun;83(8):701-715. doi: 10.1007/s40265-023-01880-x. Epub 2023 May 11. PMID:37166619;PMCID:PMC10173235.) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10173235/
Figure 2 clinical and trichoscopy pictures of a 27-year-old male patients with moderate AGA before and after 6 months of topical finasteride treatment.
Oral Bicalutamide
Bicalutamide is a new nonsteroidal, pure antiandrogen drug with a more favorable safety and tolerability profile than flutamide. In a retrospective analysis involving 17 female patients with FPHL (female pattern hair loss), who were administered 50 mg of bicalutamide daily or every other day for a duration of 24 weeks, 57% of the patients experienced significant hair regrowth. Additionally, 12.5% of the patients exhibited a mild increase in liver enzyme levels. A retrospective assessment of 316 women who were prescribed oral bicalutamide demonstrated that the drug is generally well-tolerated. The primary observed side effect was a mild elevation in liver enzyme levels in nine patients, which resolved without necessitating a change in dosage for four out of these nine patients. Notably, two patients who had previously discontinued flutamide due to colitis development tolerated bicalutamide without any issues.
(Devjani S, Ezemma O, Kelley KJ, Stratton E, Senna M. Androgenetic Alopecia: Therapy Update. Drugs. 2023 Jun;83(8):701-715. doi: 10.1007/s40265-023-01880-x. Epub 2023 May 11. PMID:37166619;PMCID:PMC10173235.) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10173235/
