Management of hair loss | |
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Specialty | dermatology |
The management of hair loss, includes prevention and treatment of alopecia, baldness, and hair thinning, and regrowth of hair.
Scratching of itchy scalp may contribute to hair loss. [1]
Prevention of obesity helps. Obesity is linked to hair thinning. [2]
Oils with fatty acids that has been studied to prevent dermatitis includes: [3] [4]
The scalp must be cleaned from sebum, sweat, and dirt, prior to topical application, for agents to penetrate it.
A 2020 systemic review on agents used to treat androgenic alopecia found that: [5]
A humidifier can be used to prevent low indoor humidity during winter (especially with indoor heating), and dry season. [6]
Commonly, patients with seborrhoeic dermatitis experience mild redness, scaly skin lesions and in some cases hair loss. [7]
Low humidity can cause adverse health effects and may cause atopic dermatitis, [8] and seborrhoeic dermatitis. [9]
Combinations of finasteride, minoxidil and ketoconazole are more effective than individual use. [10]
Combination therapy of LLLT or microneedling with finasteride [11] or minoxidil demonstrated substantive increases in hair count. [12]
The topical bioavailability of synthetic medicines such as antiandrogens, as well as phytochemicals such as quercetin, has been improved with incorporation of drugs in nanoparticles, or microneedling. [13]
Treatments for the various forms of hair loss have only moderate success. [14] Three medications have evidence to support their use in male pattern hair loss: finasteride, dutasteride and minoxidil. [15] They typically work better to prevent further hair loss than to regrow lost hair. [15]
They may be used together when hair loss is progressive or further regrowth is desired after 12 months. [16] Other medications include ketoconazole, and in female androgenic alopecia spironolactone and flutamide. [17]
In June 2022, the FDA authorized baricitinib for the treatment of severe alopecia areata. [18] [19]
Minoxidil, applied topically, is widely used for the treatment of hair loss. It may be effective in helping promote hair growth in both men and women with androgenic alopecia. [20] [21] About 40% of men experience hair regrowth after 3–6 months. [22] It is the only topical product that is FDA approved in America for androgenic hair loss. [20] However, increased hair loss has been reported. [23] [24]
Finasteride is used to treat male pattern hair loss. [25] Treatment provides about 30% improvement in hair loss after six months of treatment, and effectiveness only persists as long as the drug is taken. [20] There is no good evidence for its use in women. [14] It may cause gynecomastia, erectile dysfunction and depression. [26]
Dutasteride is also used in the treatment of male pattern hair loss and appears to have better effectiveness than finasteride for the condition. [27] [28] [29] While used off-label for male pattern hair loss in most of the world, dutasteride is specifically approved for this indication in South Korea and Japan. [30] [31]
There is tentative support for spironolactone in women. [14] Due to its feminising side effects and risk of infertility it is not often used by men. [32] [33] It can also cause low blood pressure, high blood potassium, and abnormal heart rhythms. Also, women who are pregnant or trying to become pregnant generally cannot use the medication as it is a teratogen, and can cause ambiguous genitalia in newborn children. [34]
There is tentative evidence for flutamide in women; however, it is associated with relatively high rates of liver problems and strong recommendations have been made against its use. [14] [35] Like spironolactone, flutamide is typically only used by women. [36] Bicalutamide is another option for the treatment of female pattern hair loss. [37] [38] [39] It has a far lower risk of liver toxicity than flutamide and is said to have an excellent safety profile. [38] [39] [40] However, bicalutamide retains a small risk of liver toxicity and for this reason periodic liver monitoring is recommended during treatment. [38] [40]
Ketoconazole may help in women. [41] [42]
Low-level laser therapy or photobiomodulation is also referred to as red light therapy and cold laser therapy. It is a non-invasive treatment option.
LLLT is shown to increase hair density and growth in both genders. The types of devices (hat, comb, helmet) and duration did not alter the effectiveness, [43] with more emphasis to be placed on lasers compared to LEDs. [44] Ultraviolet and infrared light are more effective for alopecia areata, while red light and infrared light is more effective for androgenetic alopecia. [45]
Medical reviews suggest that LLLT is as effective or potentially more than other non invasive and traditional therapies like minoxidil and finasteride but further studies such as RCTs, long term follow up studies, and larger double blinded trials need to be conducted to confirm the initial findings. [46] [11] [47]
Using ones own cells and tissues and without harsh side effects, PRP is beneficial for alopecia areata [48] and androgenetic alopecia and can be used as an alternative to minoxidil or finasteride. [49] It has been documented to improve hair density and thickness in both genders. [50] A minimum of 3 treatments, once a month for 3 months are recommended, and afterwards a 3-6 month period of continual appointments for maintenance. [51] Factors that determine efficacy include amount of sessions, double versus single centrifugation, age and gender, and where the PRP is inserted. [52]
Future larger randomized controlled trials and other high quality studies are still recommended to be carried out and published for a stronger consensus. [46] [50] [53] Further development of a standardized practice for procedure is also recommended. [48]
Hair transplantation is a surgical technique that moves individual hair follicles from a part of the body called the donor site to bald or balding part of the body known as the recipient site. It is primarily used to treat male pattern baldness. In this condition, grafts containing hair follicles that are genetically resistant to balding are transplanted to bald scalp. It is also used to restore eyelashes, eyebrows, beard hair, chest hair, and pubic hair and to fill in scars caused by accidents or surgery such as face-lifts and previous hair transplants. Hair transplantation differs from skin grafting in that grafts contain almost all of the epidermis and dermis surrounding the hair follicle, and many tiny grafts are transplanted rather than a single strip of skin.
Since hair naturally grows in follicles in groups of 1 to 4 hairs, transplantation takes advantage of these naturally occurring follicular units. This achieves a more natural appearance by matching hair for hair through Follicular unit transplantation (FUT).
Donor hair can be harvested in two different ways. Small grafts of naturally-occurring units of one to four hairs, called follicular units, can be moved to balding areas of the hair restoration. These follicular units are surgically implanted in the scalp in very close proximity to one another and in large numbers. The grafts are obtained in one or both of the two primary methods of surgical extraction, follicular unit transplantation, colloquially referred to as "strip harvesting", or Follicular Unit Extraction (FUE), in which follicles are transplanted individually.
In FUT, a strip of skin containing many follicular units is extracted from the patient and dissected under a stereoscopic microscope. The site of the strip removal is stitched closed. Once divided into follicular unit grafts, each unit is individually inserted into small recipient sites made by an incision in the bald scalp. In the newer technique, roots are extracted from the donor area and divided into strips for transplantation. The strip, two to three millimeters thick, is isolated and transplanted to the bald scalp. [54] After surgery, a bandage is worn for two days to protect the stitched strip during healing. A small strip scar remains after healing, which can be covered by scalp hair growing over the scar. [55]
Scalp reduction is a surgical procedure in which the hairless region of the scalp of a bald man is reduced. This procedure can reduce the area of the scalp without hair. [56] [57]
Bimatoprost 0.03% has been used to grow eyebrows. [58]
The FP receptor agonist, bimatoprost, in the form of an 0.03% ophthalmic solution termed Latisse, is approved by the US Food and Drug Administration to treat hypotrichosis of the eyelashes, in particular to darken and lengthen eyelashes for cosmetic purposes. [59] Also, bimatoprost may be used to treat small or underdeveloped eyelashes. [60] [61]
Some popular plant juices sold as hair serum may instead of growing human hair actually inhibit the growth, including 6-gingerol found in ginger. [62]
A small 2002 study demonstrated that treatment twice daily for six weeks with crude onion juice from Australian brown onion, re-growth hair on alopecia areata (spot baldness) in 86.9% of the 23 participants. [63] Twice as many flavonols are found in red onion than in yellow onion. [64] Also, non-organic onions might contain pesticides on the peel and in the first scaly leaf. Compounds found in onion that stimulates hair growth:
Dietary supplements are not typically recommended. [70] Many people use unproven treatments, [15] but there is little evidence of the effectiveness of vitamins, minerals, or other dietary supplements regrowing hair or retaining hair. [14] There is no evidence for biotin (vitamin B7). [70] While lacking both evidence and expert recommendation, there is a large market for hair growth supplements, especially for products that contain biotin.
However, one small trial of saw palmetto which shows tentative benefit in those with mild to moderate androgenetic alopecia. [70] There was no good evidence for gingko, aloe vera, ginseng, bergamot, or hibiscus as of 2011. [71]
Radiation induces hair loss through damage to hair follicle stem cell progenitors and alteration of keratin expression. [72] [73] Radiation therapy has been associated with increased mucin production in hair follicles. [74]
Studies have suggested electromagnetic radiation as a therapeutic growth stimulant in alopecia. [75]
Certain hair shampoos and ointments visually thicken existing hair, without affecting the growth cycle. [76] There have also been developments in the fashion industry with wig design. The fashion accessory has also been shown to be a source of psychological support for women undergoing chemotherapy, with cancer survivors in one study describing their wig as a "constant companion". [77] Other studies in women have demonstrated a more mixed psychosocial impact of hairpiece use. [78]
Specialized tattoos, commonly known as scalp micropigmentation, can mimic the appearance of a short buzzed haircut. [79]
Type 1 and 2 5α reductase enzymes are present at pilosebaceous units in papillae of individual hair follicles. They catalyse formation of the androgens testosterone and DHT, which in turn regulate hair growth. Androgens have different effects at different follicles: they stimulate IGF-1 at facial hair, causing hair regrowth, but stimulate TGF β1, TGF β2, dickkopf1 and IL-6 at the scalp, causing hair follicle miniaturisation. [80]
Female androgenic alopecia is characterized by diffuse crown thinning without hairline recession, and like its male counterpart rarely leads to total hair loss. [81] Finasteride and minoxidil are usually first line therapy for its treatment. Other options include topical or systemic spironolactone or flutamide, although they have a high incidence of feminising side effects and are better tolerated in female androgenic hair loss.
More advanced cases may be resistant or unresponsive to medical therapy, however, and require hair transplantation. Naturally-occurring units of one to four hairs, called follicular units, are excised and moved to areas of hair restoration. These follicular units are surgically implanted in the scalp in close proximity and in large numbers. The grafts are obtained from either Follicular Unit Transplantation (FUT) – colloquially referred to as "strip harvesting" – or Follicular Unit Extraction (FUE). In the former, a strip of skin with follicular units is extracted and dissected into individual follicular unit grafts. The surgeon then implants the grafts into small incisions, called recipient sites. [55] [82] Specialized scalp tattoos can also mimic the appearance of a short buzzed haircut. [83] Androgenic alopecia also occurs in women, and more often presents as diffuse thinning without hairline recession. Like its male counterpart, the condition rarely leads to total hair loss. Treatment options are similar to those for men, although topical or systemic estrogen is used more often. [81] [84]
Latanoprost and bimatoprost are specific PGF2a analogues applied topically, and have been found to lengthen eyelashes, [85] [86] darken hair pigmentation [87] and elongate hair. [17] Bimatoprost is available as treatment for eyelash growth. [88] Latanoprost has shown ability to promote scalp hair density and pigmentation, [89] and is theorized to function at the dermal papilla. [90] A study found latanoprost ineffective on eyelashes in a patient with alopecia areata. [91] It has also been found ineffective in treatment of eyebrow hair loss. [92]
Estrogens are indirect anti-androgens and can be used to treat androgenetic hair loss in women with oral contraceptives. Systemic estrogen increases SHBG, which binds androgens, including testosterone and DHT, in turn reducing their bioavailability. Topical formulations are available in Europe. [71] Hair follicles have estrogen receptors and it is theorized that topical compounds act on them directly to promote hair growth and antagonize androgen action. Large clinical studies showing effectiveness are absent. Topical treatment is also usually unavailable in North America. [17]
There is tentative evidence for cyproterone acetate in women. [14]
In December 2012, topical application of IGF-1 in a liposomal vehicle led to thicker and more rapid hair growth in transgenic mice with androgenic alopecia. The study did not show measurable systemic levels or hematopoietic side effects, suggesting potential for use in humans. [93] Low energy radiofrequency irradiation induces IGF-1 in cultured human dermal papilla cells. [94] Adenosine stimulates dermal papillae in vitro to induce IGF-1, along with fibroblast growth factors FGF7, FGF-2 and VEGF. β-catenin transcription increased, which promotes dermal papillae as well. [94] Dietary isoflavones increase IGF production in scalp dermal papillae in transgenic mice. [95] Topical capsaicin also stimulates IGF at hair follicles via release of vanilloid receptor-1, which in turn leads to more CGRP. [96] Ascorbic acid has led to increased IGF expression in vitro. [97]
Although follicles were previously thought gone in areas of complete baldness, they are more likely dormant, as recent studies have shown the scalp contains the stem cells from which the follicles arose. [98] Research on these follicular stem cells may lead to successes in treating baldness through hair multiplication (HM), also known as hair cloning .
Per a May 2015 review, no successful strategy to generate human hair follicles, for hair regrowth, from adult stem cells has yet been reported. [99] However, in April 2016, scientists from Japan published results of their work in which they created human skin from induced pluripotent stem cells; implanted into laboratory mice, the cells generated skin with hair and glands. [100]
From 2005 to 2007, Curis and Procter & Gamble collaborated on developing a topical hedgehog agonist for hair loss; the agent did not meet safety standards, and the program was terminated. [101] [102] In 2008, researchers at the University of Bonn announced they have found the genetic basis of two distinct forms of inherited hair loss. They found the gene P2RY5 causes a rare, inherited form of hair loss called hypotrichosis simplex. It is the first receptor in humans known to play a role in hair growth. [103] [104] [105] Researchers found that disruption of the gene SOX21 in mice caused cyclical hair loss. Research has suggested SOX21 as a master regulator of hair shaft cuticle differentiation, with its disruption causing cyclical alopecia in mice models. [106] Deletion of SOX21 dramatically affects hair lipids. [107]
Alopecia areata, also known as spot baldness, is a condition in which hair is lost from some or all areas of the body. It often results in a few bald spots on the scalp, each about the size of a coin. Psychological stress and illness are possible factors in bringing on alopecia areata in individuals at risk, but in most cases there is no obvious trigger. People are generally otherwise healthy. In a few cases, all the hair on the scalp is lost, or all body hair is lost. Hair loss can be permanent, or temporary.
Hair loss, also known as alopecia or baldness, refers to a loss of hair from part of the head or body. Typically at least the head is involved. The severity of hair loss can vary from a small area to the entire body. Inflammation or scarring is not usually present. Hair loss in some people causes psychological distress.
The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between hormones, neuropeptides, and immune cells. This complex interaction induces the hair follicle to produce different types of hair as seen on different parts of the body. For example, terminal hairs grow on the scalp and lanugo hairs are seen covering the bodies of fetuses in the uterus and in some newborn babies. The process of hair growth occurs in distinct sequential stages: anagen is the active growth phase, catagen is the regression of the hair follicle phase, telogen is the resting stage, exogen is the active shedding of hair phase and kenogen is the phase between the empty hair follicle and the growth of new hair.
Telogen effluvium is a scalp disorder characterized by the thinning or shedding of hair resulting from the early entry of hair in the telogen phase. It is in this phase that telogen hairs begin to shed at an increased rate, where normally the approximate rate of hair loss is 125 hairs per day.
Alopecia universalis(AU), also known as alopecia areata universalis, is a medical condition involving the loss of all body hair, including eyebrows, eyelashes, chest hair, armpit hair, and pubic hair. It is the most severe form of alopecia areata. People with the disease are usually healthy and have no other symptoms and a normal life expectancy.
Finasteride, sold under the brand names Proscar and Propecia among others, is a medication used to treat pattern hair loss and benign prostatic hyperplasia (BPH) in men. It can also be used to treat excessive hair growth in women. It is usually taken orally but there are topical formulations for patients with hair loss, designed to minimize systemic exposure by acting specifically on hair follicles.
Trichology is the study of the hair and scalp. The term derives from Ancient Greek θρίξ (thríx), "hair" and -λογία -logia. In most jurisdictions the title of a trichologist, not the field of trichology, is considered a para-medical discipline.
Pattern hair loss is a hair loss condition that primarily affects the top and front of the scalp. In male-pattern hair loss (MPHL), the hair loss typically presents itself as either a receding front hairline, loss of hair on the crown (vertex) of the scalp, or a combination of both. Female-pattern hair loss (FPHL) typically presents as a diffuse thinning of the hair across the entire scalp.
Madarosis is a condition that results in the loss of eyelashes, and sometimes eyebrows. The term "madarosis" is derived from the ancient Greek "madaros", meaning "bald". It originally was a disease of only losing eyelashes but it currently is the loss of both eyelashes and eyebrows. Eyebrows and eyelashes are both important in the prevention of bacteria and other foreign objects from entering the eye. A majority of patients with madarosis have leprosy, and it was reported that 76% of patients with varying types of leprosy had madarosis.
Anagen effluvium is the pathologic loss of anagen or growth-phase hairs. Classically, it is caused by radiation therapy to the head and systemic chemotherapy, especially with alkylating agents.
Loose anagen syndrome, also known as loose anagen hair syndrome, is a hair disorder related to dermatology. It is characterised by the easy and pain free detachment of anagen staged hairs from the scalp. This hair condition can be spontaneous or genetically inherited.
Scarring hair loss, also known as cicatricial alopecia, is the loss of hair which is accompanied with scarring. This is in contrast to non scarring hair loss.
Central centrifugal cicatricial alopecia (CCCA), is a type of alopecia first noticed in African Americans in the 1950s and reported by LoPresti et al. in 1968 as a result of application of petrolatum followed by a stove-heated iron comb. The original theory was that the hot petrolatum would travel down to the hair root, burn the follicle, and after repetitive injury scarring would result. Later CCCA was realized to affect men and women without a history significant for use of such styling techniques. Consequently, the terms "follicular degeneration syndrome" per Sperling and Sau in 1992 and then CCCA per Olsent et al. in 2003 were evolved. Plausible contributing factors may include other African-American styling techniques such as relaxers, tight braids, heavy extensions, certain oils, gels or pomades.
Non scarring hair loss, also known as noncicatricial alopecia is the loss of hair without any scarring being present. There is typically little inflammation and irritation, but hair loss is significant. This is in contrast to scarring hair loss during which hair follicles are replaced with scar tissue as a result of inflammation. Hair loss may be spread throughout the scalp (diffuse) or at certain spots (focal). The loss may be sudden or gradual with accompanying stress.
Trichoscopy is a method of hair and scalp evaluation and is used for diagnosing hair and scalp diseases. The method is based on dermoscopy. In trichoscopy hair and scalp structures may be visualized at many-fold magnification. Currently magnifications ranging from 10-fold to 70-fold are most popular in research and clinical practice.
Frontal fibrosing alopecia is the frontotemporal hairline recession and eyebrow loss in postmenopausal women that is associated with perifollicular erythema, especially along the hairline. It is considered to be a clinical variant of lichen planopilaris.
The growth of human hair occurs everywhere on the body except for the soles of the feet, the palms of the hands, the inside of the mouth, the lips, the backs of the ears, some external genital areas, the navel, scar tissue, and, apart from eyelashes, the eyelids. Hair is a stratified squamous keratinized epithelium made of multi-layered flat cells whose rope-like filaments provide structure and strength to the hair shaft. The protein called keratin makes up hair and stimulates hair growth. Hair follows a specific growth cycle with three distinct and concurrent phases: anagen, catagen, and telogen. Each phase has specific characteristics that determine the length of the hair.
Alfatradiol, also known as 17α-estradiol and sold under the brand names Avicis, Avixis, Ell-Cranell Alpha, and Pantostin, is a weak estrogen and 5α-reductase inhibitor medication which is used topically in the treatment of pattern hair loss in men and women. It is a stereoisomer of the endogenous steroid hormone and estrogen 17β-estradiol.
Topilutamide, known more commonly as fluridil and sold under the brand name Eucapil, is an antiandrogen medication which is used in the treatment of pattern hair loss in men and women. It is used as a topical medication and is applied to the scalp. Topilutamide belongs to a class of molecules known as perfluoroacylamido-arylpropanamides.
Minoxidil sulfate, also known as minoxidil sulfate ester or minoxidil N-O-sulfate, is an active metabolite of minoxidil and is the active form of this agent. Minoxidil acts as a prodrug of minoxidil sulfate. Minoxidil sulfate is formed from minoxidil via sulfotransferase enzymes, with the predominant enzyme responsible, at least in hair follicles, being SULT1A1. Minoxidil sulfate acts as a potassium channel opener, among other actions, and has vasodilating, hypotensive, and trichogenic or hypertrichotic effects. Its mechanism of action in terms of hair growth is still unknown, although multiple potential mechanisms have been implicated.