87-431: 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. Finasteride
174-683: A Y-chromosome gene or a paternal imprinting effect. The initial programming of pilosebaceous units of hair follicles begins in utero . The physiology is primarily androgenic , with dihydrotestosterone (DHT) being the major contributor at the dermal papillae . Men with premature androgenic alopecia tend to have lower than normal values of sex hormone-binding globulin (SHBG), follicle stimulating hormone (FSH), testosterone , and epitestosterone when compared to men without pattern hair loss. Although hair follicles were previously thought to be permanently gone in areas of complete hair loss, they are more likely dormant, as recent studies have shown
261-464: A genetic mutation , causing deficiency of the 5α-reductase enzyme and male hormone dihydrotestosterone (DHT), which was found to have been the etiology behind abnormalities in male sexual development. Upon maturation, these individuals were observed to have smaller prostates which were underdeveloped, and were also observed to lack incidence of male pattern baldness. In 1975, copies of Imperato-McGinley's presentation were seen by P. Roy Vagelos , who
348-415: A 4× increased frequency which is clinically deemed significant. Abdominal obesity, hypertension and lowered high density lipoprotein were also significantly higher for younger groups. Pattern hair loss is classified as a form of non-scarring hair loss. Male-pattern hair loss begins above the temples and at the vertex ( calvaria ) of the scalp . As it progresses, a rim of hair at the sides and rear of
435-479: A 93% reduction in facial hirsutism and a 73% reduction of bodily hirsutism after 2 years of treatment. Other studies using finasteride for hirsutism have also found it to be effective. Finasteride is sometimes used in hormone replacement therapy for transgender women due to its antiandrogenic effects, in combination with a form of estrogen . However, little clinical research of finasteride use for this purpose has been conducted and evidence of safety or efficacy
522-620: A conference on birth defects. She reported on a group of intersex children in the Caribbean who appeared sexually ambiguous at birth, and were initially raised as girls, but then grew external male genitalia and other masculine characteristic after onset of puberty. These children, despite being raised as girls until puberty, were generally heterosexual, and were termed " Guevedoces " by their local community, which means "penis at twelve" in Spanish. Her research group found these children shared
609-453: A masculine attribute associated with seniority and higher social status . The condition is caused by a combination of male sex hormones (balding never occurs in castrated men) and genetic factors. Some research has found evidence for the role of oxidative stress in hair loss, the microbiome of the scalp, genetics, and circulating androgens ; particularly dihydrotestosterone (DHT). Men with early onset androgenic alopecia (before
696-407: A mean age of 62.4) are at increased risk for impotence, erectile dysfunction (ED), decreased libido, and ejaculation disorder for the first year of treatment. The rates became indistinguishable from placebo after 2–4 years and these side effects usually got better over time. Finasteride may cause persistent adverse sexual, neurological and physical effects in a subset of men. A 2019 metastudy surveyed
783-449: A month. An example of premature age effect is Werner's syndrome , a condition of accelerated aging from low-fidelity copying of mRNA. Affected children display premature androgenic alopecia. Permanent hair-loss is a result of reduction of the number of living hair matrixes. Long-term of insufficiency of nutrition is an important cause for the death of hair matrixes. Misrepair-accumulation aging theory suggests that dermal fibrosis
870-494: A mystery, but possible explanations are higher conversion of testosterone to DHT locally with age as higher levels of 5-alpha reductase are noted in balding scalp, and higher levels of DNA damage in the dermal papilla as well as senescence of the dermal papilla due to androgen receptor activation and environmental stress. Multiple cross-sectional studies have found associations between early androgenic alopecia, insulin resistance , and metabolic syndrome , with low HDL being
957-452: A potent 5α-reductase inhibitor but a weak inhibitor of 5β-reductase, the medication decreases circulating levels of 5α-reduced steroids like allopregnanolone but does not reduce concentrations of 5β-reduced steroids like pregnanolone . Pregnanolone acts as a potent GABA A receptor positive allosteric modulator similarly to allopregnanolone. The mean oral bioavailability of finasteride is approximately 65%. The absorption of finasteride
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#17327805432801044-918: A proposed post-finasteride syndrome (PFS), although some within the medical community question whether there is enough evidence to support a causal relationship between finasteride usage and PFS. Individuals claiming to experience PFS report sexual, neurological, hormonal and psychological side effects that persist for an extended period after stopping the drug. Reported symptoms include penile atrophy and tissue changes, decreased ejaculate volume and quality, reduced libido, erectile dysfunction, loss of penile sensitivity, decreased orgasm sensation, dry skin, metabolic changes, muscle and strength loss, gynecomastia , depression, anxiety, panic attacks, insomnia, anhedonia , concentration problems, memory impairment and suicidal ideation . A meta-analysis found significant association between finasteride use and post-discontinuation depression, suicidal ideation, and sexual dysfunction, but
1131-476: Is 76 L. Its plasma protein binding is 90%. The drug has been found to cross the blood–brain barrier , whereas levels in semen were found to be undetectable. Finasteride is extensively metabolized in the liver , first by hydroxylation via CYP3A4 and then by aldehyde dehydrogenase . It has two major metabolites , which are the tert - butyl side chain monohydroxylated and monocarboxylic acid metabolites. These metabolites show approximately 20% of
1218-573: Is a 5α-reductase inhibitor and therefore an antiandrogen . It works by decreasing the production of dihydrotestosterone (DHT) by about 70%. In addition to DHT, finasteride also inhibits the production of several anticonvulsant neurosteroids including allopregnanolone , androstanediol , and tetrahydrodeoxycorticosterone . Adverse effects from finasteride are rare in men with already enlarged prostates; however, some men experience sexual dysfunction , depression , and breast enlargement . In some men, sexual dysfunction may persist after stopping
1305-486: Is a synthetic androstane steroid and 4-azasteroid . It is an analogue of androgen steroid hormones like testosterone and DHT. As an unconjugated steroid, finasteride is a highly lipophilic compound. In 1942, James Hamilton observed that prepubertal castration prevents the later development of male pattern baldness in mature men. In 1974, Julianne Imperato-McGinley of Cornell Medical College in New York attended
1392-490: Is a medication of the 5α-reductase inhibitors (5-ARIs) class. By inhibiting type II 5-AR, finasteride prevents the conversion of testosterone to dihydrotestosterone in various tissues including the scalp. Increased hair on the scalp can be seen within three months of starting finasteride treatment and longer-term studies have demonstrated increased hair on the scalp at 24 and 48 months with continued use. Treatment with finasteride more effectively treats male-pattern hair loss at
1479-538: Is associated with seniority and higher social ranking, giving them increased sexual capital . This is similar to the white stripe seen on male silver-back gorillas , associated with their advanced age and higher social ranking. The genetic evidence did not support this hypothesis in African populations, suggesting that within Africa, the evolutionary pressure for scalp hair (to protect against harsh sunlight) outweighed
1566-415: Is associated with the progressive hair-loss and hair-whitening in old people. With age, the dermal layer of the skin has progressive deposition of collagen fibers, and this is a result of accumulation of Misrepairs of derma. Fibrosis makes the derma stiff and makes the tissue have increased resistance to the walls of blood vessels. The tissue resistance to arteries will lead to the reduction of blood supply to
1653-474: Is beneficial for alopecia areata and androgenetic alopecia and can be used as an alternative to minoxidil or finasteride. It has been documented to improve hair density and thickness in both genders. 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. Factors that determine efficacy include amount of sessions, double versus single centrifugation, age and gender, and where
1740-436: Is effective in the treatment of hidradenitis suppurativa in girls and women. Finasteride and other antiandrogens might be useful in the treatment of obsessive–compulsive disorder , but more research is needed. Pattern hair loss Pattern hair loss (also known as androgenetic alopecia ( AGA ) ) is a hair loss condition that primarily affects the top and front of the scalp . In male-pattern hair loss ( MPHL ),
1827-528: Is its DCF Tooltip Dénomination Commune Française . It is also known by its former developmental code names MK-906 , YM-152 , and L-652,931 . Finasteride is marketed primarily under the brand names Propecia, for pattern hair loss, and Proscar, for BPH, both of which are products of Merck & Co . There is 1 mg of finasteride in Propecia and 5 mg in Proscar. Merck's patent on finasteride for
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#17327805432801914-768: Is limited. Moreover, caution has been recommended when prescribing finasteride to transgender women, as finasteride may be associated with side effects such as depression, anxiety, and suicidal ideation, symptoms that are particularly prevalent in the transgender population and in others at high risk already. A 2010 Cochrane review of finasteride for BPH found that, in men with a weighted mean age of 62.4, adverse effects are rare in men with already enlarged prostates; “nevertheless, men taking finasteride are at increased risk for impotence, erectile dysfunction, decreased libido, and ejaculation disorder, versus placebo." As of 2016, fresh evidence suggested such effects, along with disturbed neurosteroid production, may persist after finasteride use
2001-423: Is little evidence to support the use of lasers to treat male-pattern hair loss. The same applies to special lights. Dietary supplements are not typically recommended. A 2015 review found a growing number of papers in which plant extracts were studied but only one randomized controlled clinical trial, namely a study in 10 people of saw palmetto extract . A 2023 study on genetically engineered mice published in
2088-806: Is low at about 1.5%. Depressive symptoms and suicidality have been reported. Use of finasteride is associated with an increased risk of sexual dysfunction including erectile dysfunction , decreased libido and ejaculatory dysfunction. Sexual adverse effects of finasteride and dutasteride have been linked to lower quality of life and ability to maintain an intimate relationship, and can cause stress in relationships. The adverse effect profiles of finasteride are somewhat different for its indications of hair loss and BPH. The most common adverse effects of finasteride taken for hair loss are: decrease in sex drive, erectile dysfunction and decrease in amount of semen. In addition, finasteride has been reported in case reports to cause sexual problems which persist after stopping
2175-422: Is more effective for androgenetic alopecia. 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. Using ones own cells and tissues and without harsh side effects, PRP
2262-551: Is most commonly formed at the tissue level by 5α-reduction of testosterone. The genetic corollary that codes for this enzyme has been discovered. Prolactin has also been suggested to have different effects on the hair follicle across gender. Also, crosstalk occurs between androgens and the Wnt-beta-catenin signaling pathway that leads to hair loss. At the level of the somatic stem cell , androgens promote differentiation of facial hair dermal papillae, but inhibit it at
2349-524: Is most dependent on intrahepatic fat, which can be measured by MRI in and out of phase imaging sequences. Serum indices of hepatic function and surrogate markers for diabetes, previously used, show less correlation with SHBG by comparison. Female patients with mineralocorticoid resistance present with androgenic alopecia. IGF levels have been found lower in those with metabolic syndrome. Circulating serum levels of IGF-1 are increased with vertex balding, although this study did not look at mRNA expression at
2436-615: Is no significant difference in efficiency between 2% and 5% formulations. Finasteride was shown to be no more effective than placebo based on low-quality studies. The effectiveness of laser-based therapies is unclear. Bicalutamide , an antiandrogen , is another option for the treatment of female pattern hair loss. More advanced cases may be resistant or unresponsive to medical therapy 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
2523-411: Is no specific recommended antidote for finasteride overdose. No significant drug interactions have been observed between finasteride and a limited selection of medications. Finasteride is a 5α-reductase inhibitor . It is specifically a selective inhibitor of the type II and III isoforms of the enzyme . By inhibiting these two isozymes of 5α-reductase, finasteride reduces the formation of
2610-435: Is not affected by food. At steady-state with 1 mg/day finasteride, mean peak concentrations of finasteride were 9.2 ng/mL (25 nmol/L). Conversely, following a single 5 mg dose of finasteride, mean peak levels of finasteride were 37 ng/mL (99 nmol/L), and plasma concentrations increased by 47–54% following 2.5 weeks of continued daily administration. The volume of distribution of finasteride
2697-464: Is not clear how this causes hair to grow. Other treatments include tretinoin combined with minoxidil, ketoconazole shampoo, dermarolling ( Collagen induction therapy ), spironolactone , alfatradiol , topilutamide (fluridil), topical melatonin , and intradermal and intramuscular botulinum toxin injections to the scalp. There is evidence supporting the use of minoxidil as a safe and effective treatment for female pattern hair loss, and there
Finasteride - Misplaced Pages Continue
2784-470: Is not well-studied and may result in birth defects if taken during pregnancy. By the age of 50, pattern hair loss affects about half of males and a quarter of females. It is the most common cause of hair loss . Both males aged 40–91 and younger male patients of early onset AGA (before the age of 35), had a higher likelihood of metabolic syndrome (MetS) and insulin resistance. With younger males, studies found metabolic syndrome to be at approximately
2871-506: Is related to being an increased risk factor for cardiovascular diseases, glucose metabolism disorders, type 2 diabetes , and enlargement of the prostate . A number of hormonal changes occur with aging: This decrease in androgens and androgen receptors, and the increase in SHBG are opposite the increase in androgenic alopecia with aging. This is not intuitive, as testosterone and its peripheral metabolite, DHT, accelerate hair loss, and SHBG
2958-414: Is stopped. Finasteride is contraindicated in pregnancy. The Food and Drug Administration advises that donation of blood or plasma be deferred for at least one month after taking the last dose of finasteride. The FDA has added a warning to 5α-reductase inhibitors concerning an increased risk of high-grade prostate cancer , as the treatment of BPH lowers PSA ( prostate-specific antigen ), which could mask
3045-435: Is the only keratin that is regulated by androgens. This sensitivity to androgens was acquired by Homo sapiens and is not shared with their great ape cousins. Although Winter et al. found that KRT37 is expressed in all the hair follices of chimpanzees, it was not detected in the head hair of modern humans. As androgens are known to grow hair on the body, but decrease it on the scalp, this lack of scalp KRT37 may help explain
3132-425: Is thought to be protective. The ratio of T/SHBG, DHT/SHBG decreases by as much as 80% by age 80, in numeric parallel to hair loss, and approximates the pharmacology of antiandrogens such as finasteride . Free testosterone decreases in men by age 80 to levels double that of a woman at age 20. About 30% of normal male testosterone level, the approximate level in females, is not enough to induce alopecia; 60%, closer to
3219-413: Is typically experienced as a "moderately stressful condition that diminishes body image satisfaction". However, although most men regard baldness as an unwanted and distressing experience, they usually are able to cope and retain integrity of personality. Although baldness is not as common in women as in men, the psychological effects of hair loss tend to be much greater. Typically, the frontal hairline
3306-533: The 5α-reductase type I isoenzyme, with more than 100-fold less inhibitory potency for type I as compared to type II ( IC 50 Tooltip Half-maximal inhibitory concentration = 313 nM and 11 nM, respectively). This is in contrast to inhibitors of all three isoenzymes of 5α-reductase like dutasteride , which can reduce DHT levels in the entire body by more than 99%. In addition to inhibiting 5α-reductase, finasteride has also been found to competitively inhibit 5β-reductase (AKR1D1). However, its affinity for
3393-773: The androgen receptor . Finasteride results in a decrease of circulating DHT levels by about 65–70% with an oral dosage of 5 mg/day and of DHT levels in the prostate gland by up to 80–90% with an oral dosage of 1 or 5 mg/day. In parallel, circulating levels of testosterone increase by approximately 10%, while local concentrations of testosterone in the prostate gland increase by about 7-fold and local testosterone levels in hair follicles increase by around 27–53%. An oral dosage of finasteride of only 0.2 mg/day has been found to achieve near-maximal suppression of DHT levels (68.6% for 0.2 mg/day relative to 72.2% for 5 mg/day). Finasteride does not completely suppress DHT production because it lacks significant inhibitory effects on
3480-554: The crown than male-pattern hair loss at the front of the head and temples. Dutasteride is a medication in the same class as finasteride but inhibits both type I and type II 5-alpha reductase. Dutasteride is approved for the treatment of male-pattern hair loss in Korea and Japan , but not in the United States. However, it is commonly used off-label to treat male-pattern hair loss. Minoxidil dilates small blood vessels; it
3567-416: The potent androgen dihydrotestosterone (DHT) from its precursor testosterone in certain tissues in the body such as the prostate gland , skin , and hair follicles . As such, finasteride is a type of antiandrogen , or more specifically, an androgen synthesis inhibitor . However, some authors do not define finasteride as an "antiandrogen," a term which can refer more specifically to antagonists of
Finasteride - Misplaced Pages Continue
3654-483: The PRP is inserted. Future larger randomized controlled trials and other high quality studies are still recommended to be carried out and published for a stronger consensus. Further development of a standardized practice for procedure is also recommended. Many people use unproven treatments. Regarding female pattern alopecia, there is no evidence for vitamins , minerals, or other dietary supplements. As of 2008, there
3741-573: The age of 35) have been deemed the male phenotypic equivalent for polycystic ovary syndrome (PCOS). The cause in female pattern hair loss remains unclear; androgenetic alopecia for women is associated with an increased risk of polycystic ovary syndrome (PCOS). Management may include simply accepting the condition or shaving one's head to improve the aesthetic aspect of the condition. Otherwise, common medical treatments include minoxidil , finasteride , dutasteride , or hair transplant surgery . Use of finasteride and dutasteride in women
3828-449: The amount found in elderly men, is sufficient. The testicular secretion of testosterone perhaps "sets the stage" for androgenic alopecia as a multifactorial diathesis stress model , related to hormonal predisposition, environment, and age. Supplementing eunuchs with testosterone during their second decade, for example, causes slow progression of androgenic alopecia over many years, while testosterone late in life causes rapid hair loss within
3915-484: The amount of terminal hairs in the anagen phase by inhibiting and sometimes reversing miniaturization of the hair follicle. Finasteride is most effective on the crown but can reduce hair loss in all areas of the scalp. Finasteride has also been tested for pattern hair loss in women; however, the results were no better than placebo. Finasteride is less effective in the treatment of scalp hair loss than dutasteride . In males aged 55 years old and over finasteride decreases
4002-521: The appearance of a short, buzzed haircut. 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, with more emphasis to be placed on lasers compared to LEDs. Ultraviolet and infrared light are more effective for alopecia areata, while red light and infrared light
4089-493: The association, finasteride improves glucose metabolism and decreases glycated hemoglobin HbA1c , a surrogate marker for diabetes mellitus. The low SHBG seen with premature androgenic alopecia is also associated with, and likely contributory to, insulin resistance, and for which it still is used as an assay for pediatric diabetes mellitus. Obesity leads to upregulation of insulin production and decrease in SHBG. Further reinforcing
4176-406: The biomedical research community, have concluded based on the available evidence, that it represents a real and serious condition. There is no known underlying biological mechanism for the proposed syndrome, and its incidence is unclear. A lack of clear diagnostic criteria and the variable reporting fraction in different health-care settings make the problem challenging to evaluate. As of 2016, Merck
4263-467: The blood bound to a large protein whose production is also dependent on GH. GH release is dependent on normal thyroid hormone. During the sixth decade of life, GH decreases in production. Because growth hormone is pulsatile and peaks during sleep, serum IGF is used as an index of overall growth hormone secretion. The surge of androgens at puberty drives an accompanying surge in growth hormone. The expression of insulin resistance and metabolic syndrome, AGA
4350-485: The brand name Propecia. It was the first 5α-reductase inhibitor to be introduced and was followed by dutasteride in 2001. The first study of finasteride in the treatment of hirsutism in women was published in 1994. Finasteride is the generic name of the drug and its INN Tooltip International Nonproprietary Name , USAN Tooltip United States Adopted Name , BAN Tooltip British Approved Name , and JAN Tooltip Japanese Accepted Name , while finastéride
4437-708: The component of metabolic syndrome with highest association. Linolenic and linoleic acids, two major dietary sources of HDL, are 5 alpha reductase inhibitors . Premature androgenic alopecia and insulin resistance may be a clinical constellation that represents the male homologue, or phenotype , of polycystic ovary syndrome . Others have found a higher rate of hyperinsulinemia in family members of women with polycystic ovarian syndrome. With early-onset AGA having an increased risk of metabolic syndrome, poorer metabolic profiles are noticed in those with AGA, including metrics for body mass index , waist circumference, fasting glucose , blood lipids , and blood pressure. In support of
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#17327805432804524-607: The development of prostate cancer. Although overall incidence of male breast cancer in clinical trials for finasteride 5 mg was not increased, there are post-marketing reports of breast cancer in association with its use, though available evidence does not provide clarity as to whether there is a causative relationship between finasteride and these cancers. A 2018 meta-analysis found no higher risk of breast cancer with 5α-reductase inhibitors. Some men develop gynecomastia (breast development or enlargement) following finasteride usage. The risk of gynecomastia with 5α-reductase inhibitors
4611-707: The different isozymes of 5α-reductase appear to be widely expressed, with notable tissues including the prostate gland, seminal vesicles , testes , epididymides , skin, hair follicles, liver , kidneys , and brain , among others. By inhibiting 5α-reductase and thus preventing DHT production, finasteride reduces androgen signaling in tissues like the prostate gland and the scalp. In the prostate, this reduces prostate volume, which improves BPH and reduces risk of prostate cancer. Finasteride reduces prostate volume by 20 to 30% in men with benign prostatic hyperplasia. Inhibition of 5α-reductase also reduces epididymal weight, and decreases motility and normal morphology of spermatozoa in
4698-666: The differential requires exclusion of other causes of hair loss, and assessing for the typical progressive hair loss pattern of androgenic alopecia. Trichoscopy can be used for further evaluation. Biopsy may be needed to exclude other causes of hair loss, and histology would demonstrate perifollicular fibrosis. The Hamilton–Norwood scale has been developed to grade androgenic alopecia in males by severity. Combinations of finasteride, minoxidil and ketoconazole are more effective than individual use. Combination therapy of LLLT or microneedling with finasteride or minoxidil demonstrated substantive increases in hair count. Finasteride
4785-403: The drug showed significant sexual adverse effects such as erectile dysfunction and less sexual desire, in particular when obstructive symptoms due to an enlarged prostate were present. Finasteride is also used to treat male pattern baldness (androgenic alopecia) in men, a condition that develops in up to 80% of Caucasian men aged 70 and over. In the United States, finasteride and minoxidil are
4872-414: The enzyme is substantially less than for 5α-reductase (an order of magnitude less than for 5α-reductase type I ) and hence is unlikely to be of clinical significance. As of 2012, the tissues in which the different isozymes of 5α-reductase are expressed are not fully clear. This is because different investigators have obtained varying results with different reagents , methods, and tissues examined. However,
4959-578: The epididymis. Neurosteroids like 3α-androstanediol (derived from DHT) and allopregnanolone (derived from progesterone ) activate the GABA A receptor in the brain ; because finasteride prevents the formation of neurosteroids, it functions as a neurosteroidogenesis inhibitor and may contribute to a reduction of GABA A activity. Reduction of GABA A receptor activation by these neurosteroids has been implicated in depression , anxiety , and sexual dysfunction . In accordance with finasteride being
5046-409: The face, but can suppress it at the temples and scalp vertex, a condition that has been referred to as the 'androgen paradox'. Men with androgenic alopecia typically have higher 5α-reductase , higher total testosterone, higher unbound/free testosterone, and higher free androgens, including DHT. 5-alpha-reductase converts free testosterone into DHT, and is highest in the scalp and prostate gland. DHT
5133-559: The follicle itself. Locally, IGF is mitogenic at the dermal papillae and promotes elongation of hair follicles. The major site of production of IGF is the liver, although local mRNA expression at hair follicles correlates with increase in hair growth. IGF release is stimulated by growth hormone (GH). Methods of increasing IGF include exercise, hypoglycemia, low fatty acids, deep sleep (stage IV REM ), estrogens , and consumption of amino acids such as arginine and leucine . Obesity and hyperglycemia inhibit its release. IGF also circulates in
5220-479: The front due to thinning of hair. In most cases, receding hairline is the first starting point; the hairline starts moving backwards from the front of the head and the sides. The cause of pattern hair loss is not yet fully understood. It appears to be the result of genetic changes that make the activity of hair follicles on the scalp become sensitive to the presence of androgenic hormones, cholesterol , and proteins such as insulin-like growth factor . KRT37
5307-562: The hair loss typically presents itself as either a receding front hairline, loss of hair on the crown and 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. Genetic research has identified alleles associated with male pattern hair loss. These alleles appear to be undergoing positive sexual selection in European and East Asian populations, as male pattern baldness may be seen as
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#17327805432805394-448: The head remains. This has been referred to as a " Hippocratic wreath", and rarely progresses to complete baldness. Female-pattern hair loss more often causes diffuse thinning without hairline recession; similar to its male counterpart, female androgenic alopecia rarely leads to total hair loss . The Ludwig scale grades severity of female-pattern hair loss. These include Grades 1, 2, 3 of balding in women based on their scalp showing in
5481-485: The inhibitory activity of finasteride on 5α-reductase. Hence, the metabolites of finasteride are not particularly active. The drug has a terminal half-life of 5 to 6 hours in adult men (18–60 years of age) and a terminal half-life of 8 hours or more in elderly men (more than 70 years of age). It is eliminated as its metabolites 57% in the feces and 40% in the urine . Finasteride, also known as 17β-( N -tert-butylcarbamoyl)-4-aza-5α-androst-1-en-3-one,
5568-434: The journal PNAS found that increasing production of a particular microRNA in hair follicle stem cells, which naturally harden with age, softened the cells and stimulated hair growth. The authors of the study said the next research step is to introduce the microRNA into the stem cells using nanoparticles applied directly to the skin, with the goal of developing a similar topical application for humans. Androgenic alopecia
5655-442: The last dose of finasteride. The UK also has a one-month deferral period. Preliminary research suggests that topical finasteride may be effective in the treatment of pattern hair loss . Topical finasteride, like the oral preparation, reduces serum DHT. DHT may be involved in the cause of acne , and 5α-reductase inhibitors might be effective in the treatment of the condition. A small retrospective study reported that finasteride
5742-517: The literature on the reversibility of finasteride's side effects. It identified three studies which demonstrated full reversibility of side effects and eleven that describe patients with irreversible adverse events. The findings were most convincing in a retrospective review of about 12,000 patients that 1.4% of the cohort developed persistent ED (ED lasting longer than 90 days post-withdrawal). Reports of long-term, post-discontinuation adverse effects in some fraction of former finasteride users have led to
5829-433: The local tissue including the papillas. Dermal fibrosis is progressive; thus the insufficiency of nutrition to papillas is permanent. Senile hair-loss and hair-whitening are partially a consequence of the fibrosis of the skin. The diagnosis of androgenic alopecia can be usually established based on clinical presentation in men. In women, the diagnosis usually requires more complex diagnostic evaluation. Further evaluation of
5916-612: The medication. A 2012 update to the FDA label noted reports of decreased sex drive, problems with ejaculation and difficulty achieving an erection which continued after stopping the medication. The update also referenced reports of testicular pain and "male infertility and/or poor quality of semen." The most common adverse sexual effects of finasteride for BPH are: trouble getting or keeping an erection, decrease in sex drive, decreased volume of ejaculate and ejaculation disorders. A 2010 Cochrane review found that men taking finasteride for BPH (with
6003-473: The medication. It may also hide the early symptoms of certain forms of prostate cancer . Finasteride was patented in 1984 and approved for medical use in 1992. It is available as a generic medication . In 2022, it was the 73rd most commonly prescribed medication in the United States, with more than 9 million prescriptions. Finasteride has been used for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate and for
6090-418: The only two FDA approved drugs for the treatment of male pattern hair loss as of 2017. Treatment with finasteride slows further hair loss and provides about 30% improvement in hair loss after six months of treatment, with effectiveness persisting as long as the drug is taken. Taking finasteride leads to a reduction in scalp and serum DHT levels; by lowering scalp levels of DHT, finasteride can maintain or increase
6177-536: The paradoxical nature of Androgenic alopecia as well as the fact that head hair anagen cycles are extremely long. Male-pattern hair loss appears to be undergoing positive sexual selection in European and Asian populations. Male pattern hair loss may be seen as an expression of masculine sexual dimorphism rather than a disorder. Because of this, it is hypothesized that men with male pattern hair loss may be favored by heterosexual women as mates, because their hair loss
6264-463: The quality of evidence was limited. The status of PFS as a legitimate and distinct medical pathology remains a subject of debate. A 2019 editorial in The BMJ called post-finasteride syndrome "ill defined and controversial". Some have argued that it has common features with other self-diagnosed "mystery syndromes" such as Morgellons or multiple chemical sensitivity , while others, including some in
6351-1102: The relationship, SHBG is downregulated by insulin in vitro , although SHBG levels do not appear to affect insulin production. In vivo , insulin stimulates both testosterone production and SHBG inhibition in normal and obese men. The relationship between SHBG and insulin resistance has been known for some time; decades prior, ratios of SHBG and adiponectin were used before glucose to predict insulin resistance. Patients with Laron syndrome , with resultant deficient IGF, demonstrate varying degrees of alopecia and structural defects in hair follicles when examined microscopically. Because of its association with metabolic syndrome and altered glucose metabolism, both men and women with early androgenic hair loss should be screened for impaired glucose tolerance and diabetes mellitus II. Measurement of subcutaneous and visceral adipose stores by MRI , demonstrated inverse association between visceral adipose tissue and testosterone/DHT, while subcutaneous adipose correlated negatively with SHBG and positively with estrogen. SHBG association with fasting blood glucose
6438-476: The risk of developing certain rare but aggressive forms of prostate cancer (27% risk increase), although not all studies have observed this. No impact of 5-α-reductase inhibitor on survival has been found in people with prostate cancer. Finasteride has been found to be effective in the treatment of hirsutism (excessive facial and/or body hair growth) in women. In a study of 89 women with hyperandrogenism due to persistent adrenarche syndrome , finasteride produced
6525-550: The risk of low-grade prostate cancer but may increase the risk of high-grade prostate cancer and has no effect on overall survival. A 2010 review found a 25% reduction in the risk of prostate cancer with 5α-reductase inhibitor. A follow-up study of the Medicare claims of participants in a 10-year Prostate Cancer Prevention Trial suggests the reduction in prostate cancer is maintained even after discontinuation of treatment. However, 5α-reductase inhibitors have been found to increase
6612-489: The scalp contains the stem cell progenitor cells from which the follicles arose. Transgenic studies have shown that growth and dormancy of hair follicles are related to the activity of insulin-like growth factor (IGF) at the dermal papillae, which is affected by DHT. Androgens are important in male sexual development around birth and at puberty. They regulate sebaceous glands , apocrine hair growth, and libido. With increasing age, androgens stimulate hair growth on
6699-482: The scalp in close proximity and in large numbers. The grafts are obtained from either follicular unit transplantation (FUT) or follicular unit extraction (FUE). In the former, a strip of skin with follicular units is extracted and dissected into individual follicular unit grafts, and in the latter individual hairs are extracted manually or robotically. The surgeon then implants the grafts into small incisions, called recipient sites. Cosmetic scalp tattoos can also mimic
6786-470: The scalp, leading to catagenic miniaturization. Hair follicles in anaphase express four different caspases . Significant levels of inflammatory infiltrate have been found in transitional hair follicles. Interleukin 1 is suspected to be a cytokine mediator that promotes hair loss. The fact that hair loss is cumulative with age while androgen levels fall as well as the fact that finasteride does not reverse advanced stages of androgenetic alopecia remains
6873-713: The scalp. Other research suggests the enzyme prostaglandin D2 synthase and its product prostaglandin D2 (PGD2) in hair follicles as contributive. These observations have led to study at the level of the mesenchymal dermal papillae. Types 1 and 2 5α reductase enzymes are present at pilosebaceous units in papillae of individual hair follicles . They catalyze formation of the androgen dihydrotestosterone from testosterone, which in turn regulate hair growth. Androgens have different effects at different follicles: they stimulate IGF-1 at facial hair, leading to growth, but can also stimulate TGF β1 , TGF β2 , dickkopf1 , and IL-6 at
6960-435: The selective benefits of male pattern hair loss. Although it is generally accepted that male pattern baldness follows a pattern of autosomal dominant inheritance, more recent research has shown that approximately 80% of bald men have bald fathers . This is greater than would be expected if pattern balding were a purely autosomal trait, and may suggest that there is an important paternal route of inheritance, either through
7047-589: The treatment of BPH expired in June 2006. Merck was awarded a separate patent for the use of finasteride to treat pattern hair loss and it expired in November 2013. Finasteride is also marketed under a variety of other brand names throughout the world. From 2005 to 2009, the World Anti-Doping Agency banned finasteride because it was discovered that the drug could be used to mask steroid abuse. It
7134-425: The treatment of male pattern hair loss (androgenetic alopecia) in men. Physicians sometimes prescribe finasteride for the treatment of benign prostatic hyperplasia, informally known as an enlarged prostate . Finasteride may improve the symptoms associated with BPH such as difficulty urinating, getting up during the night to urinate, hesitation at the start and end of urination, and decreased urinary flow. The use of
7221-807: Was a defendant in approximately 1,370 product liability lawsuits which had been filed by customers alleging they have experienced persistent sexual side effects following cessation of treatment with finasteride. Most cases were settled by 2018 when Merck paid a lump sum of US$ 4.3 million to be distributed. As of September 2019, 25 cases remained outstanding in the United States. In 2019, Reuters reported that faulty redactions in court documents revealed allegations from plaintiffs that Merck had known of persistent side effects in their original clinical trials but chose not to disclose them in warning labels. Finasteride has been studied in humans at single doses of up to 400 mg and at continuous dosages of up to 80 mg/day for three months, without adverse effects observed. There
7308-466: Was approved by the U.S. Food and Drug Administration (FDA) for treatment of BPH, which Merck marketed under the brand name Proscar. Rasmusson and Brooks were awarded IPO's "Inventor of the Year" award in 1993 for their work on finasteride. In 1997, Merck was successful in obtaining FDA approval for a second indication of finasteride (1 mg) for treatment of male pattern hair loss, which was marketed under
7395-454: Was effective in the treatment of acne in women with normal testosterone levels. A randomized controlled trial found that finasteride was less effective than flutamide or an ethinylestradiol/cyproterone acetate birth control pill in the treatment of acne in women with high androgen levels . Androgens and estrogens may be involved in the cause of hidradenitis suppurativa (acne inversa). Two case series have reported that finasteride
7482-462: Was removed from the list effective 1 January 2009, after improvements in testing methods made the ban unnecessary. Athletes who used finasteride and were banned from international competition include skeleton racer Zach Lund , bobsledder Sebastien Gattuso , footballer Romário , and ice hockey goaltender José Théodore . The US Food and Drug Administration advises that donation of blood or plasma be deferred for at least one month after taking
7569-625: Was then serving as Merck 's basic-research chief. He was intrigued by the notion that decreased levels of DHT led to the development of smaller prostates. Dr. Vagelos then sought to create a drug which could mimic the condition found in these children to treat older men who had benign prostatic hyperplasia. Finasteride was developed by Merck under the code name MK-906. A team led by chemist Gary Rasmusson and biologist Jerry Brooks developed potential 5α-reductase inhibitors based on transition state inhibitors, using an iterative process of molecular design, testing, and redesign. In 1992, finasteride (5 mg)
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