Effectiveness and safety of the ablative fractional 2940-nm Er: YAG laser for the treatment of androgenetic alopecia.

Laser sources have established their potential effect in inducing hair regrowth. No large cohort study has evaluated the effect of ablative fractional 2940-nm erbium yttrium aluminum garnet (Er: YAG) laser in the treatment of androgenetic alopecia (AGA). To investigate the efficacy and safety of the ablative fractional 2940-nm Er: YAG laser in combination with medication therapy for the treatment of AGA. We performed a retrospective study between first July 2021 to 30th December 2021. All included patients received oral finasteride and topical minoxidil, or combined with six sessions of Er: YAG laser at 2-week intervals. Patients were divided into medication or combined therapy groups. The efficacy of the two therapies was evaluated by the investigator's Global Assessment (IGA) scores and the patient's Likert satisfaction scale at week 12 and week 24. Changes in total, terminal and villous hair count, total and terminal hair diameter, and AGA grade were also recorded. Adverse events were evaluated at each follow-up. A total of 192 male patients with AGA were included, including 67 receiving combination treatment, and 125 receiving medication treatment. At week 24, the combination treatment afforded superior outcomes in the IGA score, patient's global assessment, total and terminal hair counts, and diameters (all P<0.05). No severe adverse events were reported in both groups. The combined therapy of ablative fractional Er: YAG laser and medication was superior in treating male AGA than single medication therapy without serious adverse effects.

Telogen Effluvium - a review of the science and current obstacles.

Telogen effluvium (TE) is a common cause of diffuse non-scarring hair loss that is usually precipitated by physiological stress such as childbirth or sudden weight loss. Despite its high rate of remission, this phenomenon of sudden excessive hair loss can be very worrisome and upsetting for affected individuals and may significantly impact their quality of life. Due to the multifactorial causes and precipitants of TE, it is often challenging to diagnose and manage. Further, the mechanisms through which physiological stress influences the human hair cycle is unknown, and there are no targeted treatments for the management of TE. This review will describe the approach in making a diagnosis of TE, summarize the latest developments made in understanding the mechanisms of TE, outline the treatments tried, and recommend ways for advancing the study of this dermatological condition.

Topical RT1640 treatment effectively reverses gray hair and stem cell loss in a mouse model of radiation-induced canities.

Gray hair is a visible sign of tissue degeneration during aging. Graying is attributed to dysfunction of melanocyte stem cells (McSCs) that results in depletion of their melanin-producing progeny. This non-lethal phenotype makes the hair follicle and its pigment system an attractive model for investigating mechanisms that contribute to tissue aging and therapeutic strategies to combat this process. One potential combination therapeutic is RT1640, which is comprised of two drugs that are known to stimulate hair growth (cyclosporine A [CsA] and minoxidil), along with RT175, a non-immunosuppressive immunophilin ligand that is implicated in tissue regeneration. Using the ionizing radiation-induced acute mouse model of hair graying, we demonstrate that RT1640, over CsA alone, promotes regeneration of the hair pigment system during and following treatment. In non-irradiated mice, RT1640 is also physiologically active and successfully speeds hair growth and expands the McSC pool. It appears that this effect relies on the combined activities of the three drugs within RT1640 to simultaneously activate hair growth and McSCs as RT175 alone was insufficient to induce hair cycling in vivo, yet sufficient to drive the upregulation of the melanogenic program in vitro. This study sets the stage for further investigation into RT1640 and its components in McSC biology and, ultimately, melanocyte hypopigmentary disorders associated with disease and aging.

Comparative Evaluation of the Clinical Efficacy of PRP-Therapy, Minoxidil, and Their Combination with Immunohistochemical Study of the Dynamics of Cell Proliferation in the Treatment of Men with Androgenetic Alopecia.

Platelet-rich plasma (PRP) therapy has been considered as a promising treatment for androgenetic alopecia (AGA). The aim of the study was comparative evaluation of the clinical efficacy of PRP-therapy, minoxidil, and their combination in the treatment of men with AGA and to evaluate the effects of PRP on the proliferation of hair follicle (HF) cells in skin biopsy. MATERIALS AND METHODS: The study involved 69 men who were divided into 3 groups who received PRP therapy, minoxidil, and their combination. The clinical efficacy of the therapy was evaluated by the dynamics of morphometric of hairs. To assess cell proliferation antibodies to ß-catenin, CD34, Ki67, and to Dkk-1 were used. RESULTS: PRP treatment was more effective than minoxidil therapy (p = 0.005). Complex therapy turned out to be more effective than minoxidil monotherapy (p < 0.0001) and PRP monotherapy (p = 0.007). After applying PRP the absolute and relative values of the ß-catenin and CD34 expression area increased; an increase in Ki67+ index was also significant. CONCLUSIONS: PRP can be considered as a treatment option for AGA. Combined PRP and minoxidil use seems promising for the treatment of AGA. PRP increase in the proliferative activity of HF cells and improves hair morphology in patients with AGA.

Assessment and Treatment Outcomes of Persistent Radiation-Induced Alopecia in Patients With Cancer.

Importance: Persistent radiation-induced alopecia (pRIA) and its management have not been systematically described. Objective: To characterize pRIA in patients with primary central nervous system (CNS) tumors or head and neck sarcoma. Design, Setting, and Participants: A retrospective cohort study of patients from January 1, 2011, to January 30, 2019, was conducted at 2 large tertiary care hospitals and comprehensive cancer centers. Seventy-one children and adults diagnosed with primary CNS tumors or head and neck sarcomas were evaluated for pRIA. Main Outcomes and Measures: The clinical and trichoscopic features, scalp radiation dose-response relationship, and response to topical minoxidil were assessed using standardized clinical photographs of the scalp, trichoscopic images, and radiotherapy treatment plans. Results: Of the 71 patients included (median [range] age, 27 [4-75] years; 51 female [72%]), 64 (90%) had a CNS tumor and 7 (10%) had head and neck sarcoma. Alopecia severity was grade 1 in 40 of 70 patients (56%), with localized (29 of 54 [54%]), diffuse (13 of 54 [24%]), or mixed (12 of 54 [22%]) patterns. The median (range) estimated scalp radiation dose was 39.6 (15.1-50.0) Gy; higher dose (odds ratio [OR], 1.15; 95% CI, 1.04-1.28) and proton irradiation (OR, 5.7; 95% CI, 1.05-30.8) were associated with greater alopecia severity (P < .001), and the dose at which 50% of patients were estimated to have severe (grade 2) alopecia was 36.1 Gy (95% CI, 33.7-39.6 Gy). Predominant trichoscopic features included white patches (16 of 28 [57%]); in 15 patients, hair-shaft caliber negatively correlated with scalp dose (correlation coefficient, -0.624; P = .01). The association between hair density and scalp radiation dose was not statistically significant (-0.381; P = .16). Twenty-eight of 34 patients (82%) responded to topical minoxidil, 5% (median follow-up, 61 [interquartile range, 21-105] weeks); 4 of 25 (16%) topical minoxidil recipients with clinical images improved in severity grade. Two patients responded to hair transplantation and 1 patient responded to plastic surgical reconstruction. Conclusions and Relevance: Persistent radiation-induced alopecia among patients with primary CNS tumors or head and neck sarcomas represents a dose-dependent phenomenon that has distinctive clinical and trichoscopic features. The findings of this study suggest that topical minoxidil and procedural interventions may have benefit in the treatment of pRIA.

The hydroxypropyl-ß-cyclodextrin-minoxidil inclusion complex improves the cardiovascular and proliferative adverse effects of minoxidil in male rats: Implications in the treatment of alopecia.

The efficacy of minoxidil (MXD) ethanolic solutions (1%-5% w/v) in the treatment of androgenetic alopecia is limited by adverse reactions. The toxicological effects of repeated topical applications of escalating dose (0.035%-3.5% w/v) and of single and twice daily doses (3.5% w/v) of a novel hydroxypropyl-ß-cyclodextrin MXD GEL formulation (MXD/HP-ß-CD) and a MXD solution were investigated in male rats. The cardiovascular effects were evaluated by telemetric monitoring of ECG and arterial pressure in free-moving rats. Ultrasonographic evaluation of cardiac morphology and function, and histopathological and biochemical analysis of the tissues, were performed. A pharmacovigilance investigation was undertaken using the EudraVigilance database for the evaluation of the potential cancer-related effects of topical MXD. Following the application of repeated escalating doses of MXD solution, cardiac hypertrophy, hypotension, enhanced serum natriuretic peptides and K+ -ion levels, serum liver biomarkers, and histological lesions including renal cancer were observed. In addition, the administration of a twice daily dose of MXD solution, at SF rat vs human = 311, caused reductions in the systolic, diastolic, and mean blood pressure of the rats (-30.76 ± 3%, -28.84 ± 4%, and -30.66 ± 5%, respectively, vs the baseline; t test P < .05). These effects were not reversible following washout of the MXD solution. Retrospective investigation showed 32 cases of cancer associated with the use of topical MXD in humans. The rats treated with MXD HP-ß-CD were less severely affected. MXD causes proliferative adverse effects. The MXD HP-ß-CD inclusion complex reduces these adverse effects.

Physiology and Medical Treatments for Alopecia.

Androgenetic alopecia (AGA) is the most common hair loss disorder in men and women. The characteristic and reproducible balding pattern in AGA negatively affects self-image and the external perceptions of the balding patient. The phenotypical changes are driven by dihydrotestosterone (DHT) and its precursor testosterone. DHT induces follicle miniaturization and hair cycle changes until resulting hairs no longer extrude through the skin surface. AGA is inherited in a polygenetic pattern and is susceptible to epigenetic and environmental factors. Currently, minoxidil, finasteride, and photolaser therapy are the only Food and Drug Administration-approved medical treatments for AGA.

Topical 5% minoxidil versus topical 0.2% glyceryl trinitrate in treatment of chronic anal fissure: A randomized clinical trial.

BACKGROUND: Chronic anal fissure (CAF) is a common painful anal condition. Medical treatment of CAF involves the use of agents that induce chemical sphincterotomy. The present trial aimed to compare the efficacy and safety of topical minoxidil and glyceryl trinitrate (GTN) preparations in treatment of CAF. METHODS: Adult patients with CAF were randomly assigned to one of two equal groups; group I received topical 5% minoxidil gel and group II received topical 0.2% GTN cream. The main outcome measures were healing of anal fissure, duration to healing, relief of symptoms, and adverse effects. RESULTS: 62 patients (36 female and 26 male) were included to the study. Group I comprised 30 patients and group II comprised 32 patients. Healing of anal fissure was achieved in 23 (76.7%) patients in group I and 15 (46.9%) patients in group II (p = 0.03). The average duration to healing in group I was significantly shorter than group II (4.1 ± 1.9 vs 5.3 ± 2.7 weeks, p = 0.048). Adverse effects were recorded in 2 (6.6%) patients in group I and 13 (40.6%) patients in group II. The post-treatment pain score in the GTN group was significantly lower than the Minoxidil group. CONCLUSION: Topical 5% minoxidil gel achieved greater and quicker healing of CAF and fewer adverse effects than topical 0.2% GTN cream. Post-treatment pain scores after GTN were significantly lower than minoxidil. TRIAL REGISTRATION NUMBER: NCT03528772.

A review of the treatment of male pattern hair loss

Introduction: Androgenetic alopecia is a common hair loss disorder affecting up to 80% of males by the age of 80. It is characterized by androgen related progressive thinning of hair in a defined pattern. It results in diminished self-esteem, reduced confidence and distress in affected men, irrespective of age or stage of baldness. An effective treatment for hair baldness is needed.Areas covered: In androgenetic alopecia, hair follicles undergo progressive miniaturization. Genetic factors and androgens are key role-players in disease pathogenesis. Herein the authors review the pharmacologic treatment of androgenetic alopecia, which involves 5 alpha reductase inhibitors, minoxidil and prostaglandins. Non-pharmacologic approaches are also explored.Expert opinion: Androgenetic alopecia progresses over time and although the current available medical treatments like finasteride and minoxidil are effective in arresting the progression of the disease, they allow only partial regrowth of hair at its best. Early treatment achieves a more optimal outcome. Non-pharmacologic treatments like PRP can be considered in patients refractory to medical treatment.Abbreviations: MPHL: male pattern hair loss; AGA: androgenetic alopecia; DHT: dihydrotestosterone; 5AR: 5-alpha-reductase; VEGF: vascular endothelial growth factor; PG's: prostaglandins (PG's); PGD2R: prostaglandin D2 receptor; VPA: valproic aid; SR: Serenoa Repens; PRP: platelet-rich plasma; PDGF: platelet derived growth factor; TGF: transforming growth factor; ERK: extracellular signal-regulated kinase; PKB: protein kinase B; LLLT: low-level laser therapy; ROS: reactive oxygen species; RCT: randomized control trial; SFRP1: secreted frizzled related protein 1; DP: dermal papilla; PDE5: phosphodiesterase 5.

Randomized trial of electrodynamic microneedle combined with 5% minoxidil topical solution for the treatment of Chinese male Androgenetic alopecia.

Background: In treating androgenetic alopecia, 5% minoxidil is a commonly used topical drug. By using electrodynamic microneedle at the same time may increase absorption of minoxidil and further stimulate hair growth.Objective: A 24-week, randomized, evaluator blinded, comparative study was performed to evaluate the efficacy of treating Chinese male androgenetic alopecia using microneedle combined with 5% minoxidil topical solution. Methods: Randomized subjects received topical 5% minoxidil (group 1, n = 20), local electrodynamic microneedle treatments (group 2, n = 20), or local electrodynamic microneedle treatments plus topical 5% minoxidil (group 3, n = 20). A total of 12 microneedle treatments were performed every 2 weeks with 2ml 5% minoxidil delivery in group three during each microneedle treatment. Patient receiving topical 5% minoxidil applied 1 ml of the solution twice daily over the course of the study. A total of 60 Chinese male subjects with Norwood-Hamilton type III-VI androgenetic alopecia were treated.Results: The mean improvement in total hair density from baseline to 24 weeks was 18.8/cm2 in group 1, 23.4/cm2 in group 2, and 38.3/cm2 in group 3. The hair growth in the three groups was significantly different (P = 0.002), but there were no significant differences in toxicity found between the three groups.Conclusions: Treatment with microneedle plus topical 5% minoxidil was associated with the best hair growth.

A Randomized, Controlled Pilot Trial Comparing Platelet-Rich Plasma to Topical Minoxidil Foam for Treatment of Androgenic Alopecia in Women.

BACKGROUND: Androgenic alopecia (AGA) is a common hair loss disorder. Studies have demonstrated successful treatment with platelet-rich plasma (PRP) in men, but studies in women are few. OBJECTIVE: To evaluate PRP in the treatment of AGA in women, compared with topical minoxidil. MATERIALS AND METHODS: Twenty women with AGA received topical minoxidil for 12 weeks and injectable PRP for 12 weeks in a randomized crossover design with an 8-week washout between treatments. Standardized TrichoScan analysis and quality-of-life questionnaires were assessed at baseline and 12-week follow-up for each treatment. RESULTS: After PRP, significant increases from baseline to Week 12 in TrichoScan analysis hair count (p = .002) and vellus hair density (p = .009) occurred. However, minoxidil resulted in significant increases in hair count (p < .001), vellus hair density (p = .03), terminal hair density (p = .004), and cumulative thickness (p = .004). Several quality of life responses improved from baseline to Week 12 after PRP treatment, whereas no improvements were noted after minoxidil. CONCLUSION: Platelet-rich plasma is an effective treatment for hair regrowth in female AGA, although not as effective as minoxidil. However, the improved quality of life responses after PRP, but not minoxidil, suggest a potential overall greater degree of satisfaction with PRP. LEVELS OF EVIDENCE: I. CLINICAL TRIAL REGISTRATION: NCT03488108.

Female Androgenetic Alopecia: An Update on Diagnosis and Management.

Female androgenetic alopecia (FAGA) is a common cause of non-scarring alopecia in women. The onset may be at any age following puberty and the frequency increases with age. Clinically, it shows a diffuse hair thinning over the central scalp, while the frontal hairline is usually retained. FAGA can have a significant psychological impact, leading to anxiety and depression. For this reason, early diagnosis is very important to stop the progression of the disease. The sex hormonal milieu is the main pathogenetic mechanism studied in FAGA. The role of androgens is not clearly defined and only one-third of women with FAGA show abnormal androgen levels. Endocrinological diseases with hyperandrogenism associated with FAGA comprise polycystic ovarian syndrome (PCOS), hyperprolactinemia, adrenal hyperplasia and, rarely, ovarian and adrenal tumours. Usually the diagnosis of FAGA is made clinically. A complete clinical examination and a blood examination can reveal other signs of hyperandrogenism. Trichoscopy shows the typical hair miniaturization. A scalp biopsy can be useful when the clinical evaluation does not provide a definitive diagnosis or when cicatricial alopecias with hair loss in the distribution of FAGA or alopecia areata are suspected. FAGA is a slowly progressive disease. The goal of therapy is to stop the progression and to induce a cosmetically acceptable hair regrowth. The most important drugs are topical minoxidil and oral anti-androgens. The purpose of this review is to provide an update on FAGA and to create a guideline on diagnosis and management of this frequent hair disease, not always easily recognizable from cicatricial alopecias with a similar distribution.

Drug Delivery System Based On Minoxidil Nanoparticles Promotes Hair Growth In C57BL/6 Mice.

PURPOSE: We designed formulations based on minoxidil (MXD) nanoparticles (N-MXD) and examined whether N-MXD can increase drug delivery into the follicles. In addition, we investigated the effect of N-MXD on hair growth in C57BL/6 mice. METHODS: N-MXD (1%) was prepared as follows: methylcellulose, p-hydroxyalkylbenzoates, mannitol, and MXD were dispersed in purified water and milled using zirconia beads under refrigeration (5500 rpm, 30 s×15 times, intermittent milling). C57BL/6 mice were used to evaluate hair-growth effects. The expression levels of mRNA and protein for vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) were determined by real-time PCR and ELISA methods, respectively. RESULTS: The ratio of solid-MXD was approximately 60% in N-MXD, and the MXD nanoparticles (90-300 nm) were oblong in shape. For the design of nanomedicines, usability is important. Therefore, we measured the stability and toxicity after N-MXD treatment. No agglutination of MXD nanoparticles was detected for 2 weeks, and no redness or MXD powder residue was observed in the skin after repetitive applications of N-MXD. Next, we evaluated hair-growth effects by N-MXD treatment. MXD contents in the skin tissue from N-MXD were lower than for commercially available MXD formulations (CA-MXD). Conversely, MXD contents in the hair bulbs were higher for N-MXD than for CA-MXD, and the drug efficacy of N-MXD was also higher than that of CA-MXD. In addition, the mRNA and protein levels of IGF-1 and VEGF were enhanced by the repetitive application of N-MXD and CA-MXD, and the enhanced IGF-1 and VEGF levels were significantly higher for N-MXD than for CA-MXD. CONCLUSION: We designed a novel nanomedicine based on MXD nanoparticles and showed that N-MXD can deliver MXD into hair bulbs via hair follicles and that the therapeutic efficiency for hair growth is higher than for CA-MXD (solution type).

Laser-assisted drug delivery for the treatment of androgenetic alopecia: ablative laser fractional photothermolysis to enhance cutaneous topical delivery of platelet-rich plasma - with or without concurrent bimatoprost and/or minoxidil.

Platelet-rich plasma, which contains numerous growth factors that promote hair growth, is a nonsurgical treatment available for patients with androgenetic alopecia. However, neither the quantity nor the location and depth of platelet-rich plasma placement in the scalp is uniform; in addition, multiple painful injections are required. Vertical uniform channels from the skin surface into the dermis, created by ablative laser fractional photothermolysis, can be used to enhance the cutaneous delivery of medications. This technique - referred to as laser assisted drug delivery - may provide an efficacious means for the administration of platelet-rich plasma to the scalp. It would not only enable the uniform placement of platelet-rich plasma in the dermis (instead of inadvertently in the subcutaneous fat) of androgenetic alopecia patients' scalps, but also eliminate the injection-associated pain. In addition, the topical application of either bimatoprost or minoxidil or both could also be enhanced with laser assisted drug delivery. In conclusion, to potentially maximize the stimulation of hair growth, laser assisted drug delivery of platelet-rich plasma - with or without bimatoprost and/or minoxidil - should be considered in patients with androgenetic alopecia in order to effectively deliver the agents to the dermis where the bulge area of the hair follicles is located.

Assessment of Quality of Life and Treatment Outcomes of Patients With Persistent Postchemotherapy Alopecia.

Importance: Persistent alopecia occurs in a subset of patients undergoing chemotherapy, yet the quality of life (QOL) of these patients and their response to therapy have not been described in a large patient cohort. Objective: To characterize the clinical presentation of patients with persistent chemotherapy-induced alopecia (pCIA) or endocrine therapy-induced alopecia after chemotherapy (EIAC) and their QOL and treatment outcomes. Design, Setting, and Participants: A retrospective multicenter cohort of 192 women with cancer treated with cytotoxic agents who received a clinical diagnosis of persistent alopecia (98 with pCIA and 94 with EIAC) between January 1, 2009, and July 31, 2017, was analyzed. All patients were from the dermatology service in 2 comprehensive cancer centers and 1 tertiary-care hospital. Data on demographics, chemotherapy regimens, severity, clinical patterns, and response to hair-growth promoting agents were assessed. Data from the Hairdex questionnaire were used to assess the QOL of patients with alopecia. Main Outcomes and Measures: The clinical presentation, response to dermatologic therapy, and QOL of patients with pCIA were assessed and compared with those of patients with EIAC. Results: A total of 98 women with pCIA (median age, 56.5 years [range, 18-83 years]) and 94 women with EIAC (median age, 56 years [range, 29-84 years]) were included. The most common agents associated with pCIA were taxanes for 80 patients (82%); the most common agents associated with EIAC were aromatase inhibitors for 58 patients (62%). Diffuse alopecia was predominant in patients with pCIA compared with patients with EIAC (31 of 75 [41%] vs 23 of 92 [25%]; P = .04), with greater severity (Common Terminology Criteria for Adverse Events, version 4.0, grade 2) among patients with pCIA (29 of 75 [39%] vs 12 of 92 [13%]; P < .001). A negative emotional effect was reported by both groups. After treatment with topical minoxidil or spironolactone, moderate to significant improvement was observed for 36 of 54 patients with pCIA (67%) and for 32 of 42 patients with EIAC (76%). Conclusions and Relevance: Persistent chemotherapy-induced alopecia is frequently more severe and diffuse when compared with EIAC, and both groups of patients experienced a negative effect. A modest benefit was observed with dermatologic therapy. Additional studies are warranted to develop effective strategies for prevention and effective therapy for pCIA and EIAC.

Frontal Fibrosing Alopecia: An Update on Pathogenesis, Diagnosis, and Treatment.

Frontal fibrosing alopecia (FFA), first described by Kossard in the early 1990s, is a form of primary lymphocytic cicatricial alopecia characterized by selective involvement of the frontotemporal hairline and eyebrows. Since the original description, an increasing number of cases have been reported worldwide and the clinical aspects of the disease have been better characterized. However, the pathogenesis is still unknown and several hypotheses have been made about possible triggering factors, including hormones, neurogenic inflammation, smoking, UV filters, and ingredients in leave-on facial products. A genetic basis has also been hypothesized as the disease can occur in siblings and members of the same family. Besides its pathogenesis, research is also focused on treatment; FFA is a chronic condition and at present there is no validated or approved treatment for this disorder. Commonly prescribed topical treatments include corticosteroids, minoxidil, and calcineurin inhibitors. Systemic treatments include 5α-reductase inhibitors, hydroxychloroquine, and retinoids. Intralesional triamcinolone acetonide is also utilized, especially for the eyebrows. Other possible treatments include pioglitazone, naltrexone, tofacitinib, and lasers.

Anterior, frontal congenital triangular alopecia, redundancy in therapy without improvement.

Congenital triangular alopecia (CTA) is a benign noncicatricial localized pattern of hair loss with unknown etiology. Although referred to as "congenital," CTA may develop in adulthood. It is believed that many cases of CTA are never diagnosed or are misdiagnosed; causing the incidence to be underestimated. The present study evaluates a case of 20-year-old woman presenting with a single circular to oval area of hair-loss in the mid-frontal region of her scalp. To date, about 170 cases of CTA have been reported and we present the first case in which the alopecic patch is located in the mid-frontal region of the scalp. We present this case not only to challenge the preconceived notion that all CTAs are frontotemporal, but also to inform other practitioners about this rare condition and prevent redundant medical treatment.

Low-dose daily aspirin reduces topical minoxidil efficacy in androgenetic alopecia patients.

Topical minoxidil is the only US FDA approved OTC drug for the treatment of androgenetic alopecia (AGA). Minoxidil is a pro-drug converted into its active form, minoxidil sulfate, by the sulfotransferase enzymes in the outer root sheath of hair follicles. Previously, we demonstrated that sulfotransferase activity in hair follicles predicts response to topical minoxidil in the treatment of AGA. In the human liver, sulfotransferase activity is significantly inhibited by salicylic acid. Low-dose OTC aspirin (75-81 mg), a derivative of salicylic acid, is used by millions of people daily for the prevention of coronary heart disease and cancer. It is not known whether oral aspirin inhibits sulfotransferase activity in hair follicles, potentially affecting minoxidil response in AGA patients. In the present study, we determined the follicular sulfotransferase enzymatic activity following 14 days of oral aspirin administration. In our cohort of 24 subjects, 50% were initially predicted to be responders to minoxidil. However, following 14 days of aspirin administration, only 27% of the subjects were predicted to respond to topical minoxidil. To the best of our knowledge, this is the first study to report the effect of low-dose daily aspirin use on the efficacy of topical minoxidil.