Minoxidil was first introduced as an antihypertensive medication and the discovery of its common adverse event, hypertrichosis, led to the development of a topical formulation for promoting hair growth. To date, topical minoxidil is the mainstay treatment for androgenetic alopecia and is used as an off-label treatment for other hair loss conditions. Despite its widespread application, the exact mechanism of action of minoxidil is still not fully understood. In this article, we aim to review and update current information on the pharmacology, mechanism of action, clinical efficacy, and adverse events of topical minoxidil.

e57*References supporting this table are available from the corresponding author upon request. y Combination treatment increases the risk of QT prolongation.

Exclamation mark hairs indicate a diagnosis of AA but not pathognomonic. In addition, angulated hairs, fractured hairs forming a sharp angle along the hair shaft, appear to be typical for AA in Asians when differentiating from TTM. It is important to consider various trichoscopic findings together to establish the diagnosis of AA or TTM.

Cutaneous and systemic lupus erythematosus (SLE) commonly involves the hair and scalp. Alopecia can result from direct activity of disease on the scalp or from the state of physical stress in the form of telogen effluvium. Discoid lupus erythematosus and lupus panniculitis/profundus are known to cause scarring alopecia, while accumulation of recent studies has shown that non-scarring alopecia in SLE may have different subtypes, comprising lupus erythematosus-specific and lupus erythematosus-nonspecific changes on histology. This review aims to summarize the clinical pattern, trichoscopic, histopathological, and direct immunofluorescence features of different types of alopecia in cutaneous and systemic lupus erythematosus, as well as exploring their relationship with SLE disease activity.

Alopecia areata (AA) is a common hair loss disorder worldwide with characteristic exclamation mark hairs. Although AA is self-limited, it can last for several months or even years in some patients. Currently, there is no US Food and Drug Administration-approved treatment for AA. Many off-label treatments are available but with limited efficacy. Through a better understanding of molecular biology, many targeted therapies have emerged as new alternatives for various autoimmune diseases. Various janus kinase (JAK) and signal transducer and activator of transcription (STAT) proteins form signaling pathways, which transmit extracellular cytokine signals to the nucleus and induce DNA transcriptions. By inhibiting JAK, T-cell-mediated inflammatory responses are suppressed. Increasing evidence suggests that JAK inhibitors (JAKis) are effective in the treatment of many autoimmune diseases, including AA. Among these, several studies on tofacitinib, ruxolitinib, and baricitinib in AA had been published, demonstrating promising outcomes of these agents. Unlike oral formulations, efficacy of topical forms of tofacitinib and ruxolitinib reported in these studies is still unsatisfactory and requires improvement. This review aims to summarize evidence of the efficacy and safety of JAKis in the treatment of AA.

Low-level laser/light therapy (LLLT) has been increasingly used for promoting hair growth in androgenetic alopecia (AGA). Our institute developed a new home-use LLLT device, RAMACAP, with optimal penetrating energy, aiming to improve therapeutic efficacy and compliance. To evaluate the efficacy and safety of the new helmet-type LLLT device in the treatment of AGA, a 24week, prospective, randomized, double-blind, sham device-controlled clinical trial was conducted. Forty subjects with AGA (20 men and 20 women) were randomized to treat with a laser helmet (RAMACAP) or a sham helmet in the home-based setting for 24 weeks. Hair density, hair diameter, and adverse events were evaluated at baseline and at weeks 8, 16, and 24. Global photographic assessment for hair regrowth after 24 weeks of treatment was performed by investigators and subjects. Thirty-six subjects (19 in the laser group and 17 in the sham group) completed the study. At week 24, the laser helmet was significantly superior to the sham device for increasing hair density and hair diameter (p = 0.002 and p = 0.009, respectively) and showed a significantly greater improvement in global photographic assessment by investigators and subjects. Reported side effects included temporary hair shedding and scalp pruritus. In conclusion, the novel helmet-type LLLT device appears to be an effective treatment option for AGA in both male and female patients with minimal adverse effects. However, the limitations of this study are small sample size, no long-term follow-up data, and use of inappropriate sham devices, which do not reflect the true negative control. Trial registration: http://clinicaltrials.in.th/ index.php?tp=regtrials&menu=trialsearch&smenu=fulltext&task=search&task2=view1&id=2061, identifier TCTR20160910003.

Treatment with topical solution of 0.25% finasteride admixed with 3% minoxidil was significantly superior to 3% minoxidil solution for promoting hair growth in male androgenetic alopecia, and well tolerated.

Peroxisome proliferator-activated receptor γ (PPAR-γ) is a ligand-activated nuclear receptor that regulates the transcription of various genes. PPAR-γ plays roles in lipid homeostasis, sebocyte maturation, and peroxisome biogenesis and has shown anti-inflammatory effects. PPAR-γ is highly expressed in human sebaceous glands. Disruption of PPAR-γ is believed to be one of the mechanisms of primary cicatricial alopecia (PCA) pathogenesis, causing pilosebaceous dysfunction leading to follicular inflammation. In this review article, we discuss the pathogenesis of PCA with a focus on PPAR-γ involvement in pathogenesis of lichen planopilaris (LPP), the most common lymphocytic form of PCA. We also discuss clinical trials utilizing PPAR-agonists in PCA treatment.