Dietary supplements are not typically recommended. There is only one small trial of saw palmetto which shows tentative benefit in those with mild to moderate androgenetic alopecia. There is no evidence for biotin. Evidence for most other produces is also insufficient. There was no good evidence for gingko, aloe vera, ginseng, bergamot, or hibiscus as of 2011. While lacking both evidence and expert recommendation, there is a large market for hair growth supplements, especially for products that contain biotin.

2008 and 2012 reviews found little evidence to support the use of special lights or lasers to treat hair loss. Additionally none are approved by the FDA in America for this use. Both laser and lights appear to be safe.

A 2014 and 2016 review found tentative evidence of benefit for lasers. While another 2014 review concluded that the results are mixed, have a high risk of bias, and that its effectiveness is unclear.

Dietary supplements are not typically recommended. There is only one small trial of saw palmetto which shows tentative benefit in those with mild to moderate androgenetic alopecia. There is no evidence for biotin. Evidence for most other produces is also insufficient. There was no good evidence for gingko, aloe vera, ginseng, bergamot, hibiscus, or sorphora as of 2011.

Many people use unproven treatments. Egg oil, in Indian, Japanese, Unani (Roghan Baiza Murgh) and Chinese traditional medicine, was traditionally used as a treatment for hair loss.

Research is looking into connections between hair loss and other health issues. While there has been speculation about a connection between early-onset male pattern hair loss and heart disease, a review of articles from 1954 to 1999 found no conclusive connection between baldness and coronary artery disease. The dermatologists who conducted the review suggested further study was needed.

Environmental factors are under review. A 2007 study indicated that smoking may be a factor associated with age-related hair loss among Asian men. The study controlled for age and family history, and found statistically significant positive associations between moderate or severe male pattern hairloss and smoking status.

Vertex baldness is associated with an increased risk of coronary heart disease (CHD) and the relationship depends upon the severity of baldness, while frontal baldness is not. Thus, vertex baldness might be a marker of CHD and is more closely associated with atherosclerosis than frontal baldness.

Many people use unproven treatments. There is no evidence for vitamins, minerals, or other dietary supplements. As of 2008, there 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.

Many medications are being studied, including abatacept, MEXIS/M6S, triamcinolone, secukinumab, tralonkinumab, apremilast, botulinum toxin, INCB018424, bimatoprost, clobetasol, AS101, autologous platelet-rich plasma, topical minoxidil, and nitric oxide gel. Some of these medications are approved for other diseases, others are not available outside of studies.

In 2014, preliminary findings showing that oral ruxolitinib, a drug approved by the US Food and Drug Administration (FDA) for bone marrow disorder myelofibrosis, restored hair growth in three individuals with long-standing and severe disease. The medicine costs almost USD $10,000 a month.

Minoxidil is a growth stimulant that stimulates already-damaged hair follicles to produce normal hair. Minoxidil does not, however, provide any protection to the follicles from further DHT damage. When a follicle is destroyed by DHT, minoxidil will no longer be able to have any more regrowth effects on that follicle. Other treatments include tretinoin combined with minoxidil, ketoconazole shampoo, spironolactone, alfatradiol, and topilutamide (fluridil).

The objective assessment of treatment efficacy is very difficult and spontaneous remission is unpredictable, but if the affected area is patched, the hair may regrow spontaneously in many cases. None of the existing therapeutic options are curative or preventive.

In cases of severe hair loss, limited success has been achieved by using the corticosteroids clobetasol or fluocinonide, corticosteroid injections, or cream. The cream is not as effective and it takes longer in order to see results. Steroid injections are commonly used in sites where the areas of hair loss on the head are small or especially where eyebrow hair has been lost. Whether they are effective is uncertain. Some other medications that have been used are minoxidil, Elocon (mometasone) ointment (steroid cream), irritants (anthralin or topical coal tar), and topical immunotherapy ciclosporin, sometimes in different combinations. Topical corticosteroids frequently fail to enter the skin deeply enough to affect the hair bulbs, which are the treatment target, and small lesions typically also regrow spontaneously. Oral corticosteroids decrease the hair loss, but only for the period during which they are taken, and these drugs can cause serious side effects.

When alopecia areata is associated to celiac disease, the treatment with a gluten-free diet allows complete and permanent regrowth of scalp and other body hair in many people, but in others there are remissions and recurrences. This improvement is probably due to the normalization of the immune response as a result of gluten withdrawal from the diet.

Hypotrichosis ("" + "" + "") is a condition of abnormal hair patterns, predominantly loss or reduction. It occurs, most frequently, by the growth of vellus hair in areas of the body that normally produce terminal hair. Typically, the individual's hair growth is normal after birth, but shortly thereafter the hair is shed and replaced with sparse, abnormal hair growth. The new hair is typically fine, short and brittle, and may lack pigmentation. Baldness may be present by the time the subject is 25 years old.

Hypotrichosis is a common feature of Hallermann–Streiff syndrome as well as others. It can also be used to describe the lack of hair growth due to chemotherapy.

The opposite of hypotrichosis is hypertrichosis, where terminal hair (thick) grows in areas that would otherwise normally have vellus hair (thin), for example abnormally thick facial hair growth in women.

Hair diseases are disorders primarily associated with the follicles of the hair.

A few examples are

- Alopecia

- Bubble hair deformity

- Hair casts

- Hair loss

- hypertrichosis

- Ingrown hair

- Monilethrix

- Premature greying of hair

- Pattern hair loss

- Trichorrhexis invaginata

Many hair diseases can be associated with distinct underlying disorders.

Piedra are fungal diseases.

Hair disease may refer to excessive shedding or baldness (or both). Balding can be localised or diffuse, scarring or non-scarring. Increased hair can be due to hormonal factors (hirsutism) or non-hormonal (hypertrichosis). Scalp disorders may or may not be associated with hair loss.

Genetic forms of localized autosomal recessive hypotrichosis include:

Ultraviolet radiation is believed to contribute to the development of actinic keratoses by inducing mutations in epidermal keratinocytes, leading to proliferation of atypical cells. Therefore, preventive measures for AKs are targeted at limiting exposure to solar radiation, including:

- Limiting extent of sun exposure

- Avoid sun exposure during noontime hours when UV light is most powerful

- Using sun protection

- Frequently applying powerful sunscreens with SPF ratings greater than 30 and that also block both UVA and UVB light

- Wearing sun protective clothing such as hats, long-sleeved shirts, long skirts, or trousers

Recent research implicating human papillomavirus (HPV) in the development of AKs suggests that HPV prevention might in turn help prevent development of AKs, as UV-induced mutations and oncogenic transformation are likely facilitated in cases of active HPV infection.

Diagnostically, researchers are investigating the role of novel biomarkers to assist in determining which AKs are more likely to develop into cutaneous or metastatic SCC. Upregulation of matrix metalloproteinases (MMP) is seen in many different types of cancers, and the expression and production of MMP-7 in particular has been found to be elevated in SCC specifically. The role of serin peptidase inhibitors (Serpins) is also being investigated. SerpinA1 was found to be elevated in the keratinocytes of SCC cell lines, and SerpinA1 upregulation was correlated with SCC tumor progression "in vivo". Further investigation into specific biomarkers could help providers better assess prognosis and determine best treatment approaches for particular lesions.

In terms of treatment, a number of medications are being studied. Resiquimod is a TLR 7/8 agonist that works similarly to imiquimod, but is 10 to 100 times more potent; when used to treat AK lesions, complete response rates have range from 40 to 74%. Afamelanotide is a drug that induces the production of melanin by melanocytes to act as a protective factor against UVB radiation. It is being studied to determine its efficacy in preventing AKs in organ transplant patients who are on immunosuppressive therapy. Epidermal growth factor receptor (EGFR) inhibitors such as gefitinib, and anti-EGFR antibodies such as cetuximab are used in the treatment of various types of cancers, and are currently being investigated for potential use in the treatment and prevention of AKs.

The cat should be taken to a veterinarian. The most suspected cause of skin problems in cats will be fleas. Other causes of over-grooming are not as easily ascertained. As household antiseptics are known to be toxic to cats, veterinary antiseptics for cats can be used to treat open sores, if they do occur. Sores can also be treated with cream, oral or injected anti-inflammatories, however if the problem continues to recur it may be more cost effective to subject the cat to laboratory testing early on. It may be difficult to keep a clean dressing on a cat's belly, and an anti-lick collar is adequate to let the wound heal. If an anti lick collar is used, a soft anti-lick collar is less cumbersome, although they are less durable. If the cat wears a plastic anti-lick collar, it may use the edge of the collar to grind against existing wounds, making them worse. A soft anti lick collar will become less effective as it is kicked out of the shape by the cat's hind leg, and will need prompt replacement. The cat can sanitize the wound if the collar is removed for daily short periods of time, also giving the cat an opportunity for an overall grooming. Scratches and wounds can heal completely using this method. When the cat stops wearing the collar, thinned hair, redness of skin or cracked nipples on the cat are early indicators that the cat has started to over-groom again.

Antidepressants for cats may be suggested by a vet.

Monilethrix (also referred to as beaded hair) is a rare autosomal dominant hair disease that results in short, fragile, broken hair that appears beaded. It comes from the Latin word for necklace ("monile") and the Greek word for hair ("thrix").

The presentation may be of alopecia (baldness). Individuals vary in severity of symptoms. Nail deformities may also be present as well as hair follicle keratosis and follicular hyperkeratosis.

Where PCOS is associated with overweight or obesity, successful weight loss is the most effective method of restoring normal ovulation/menstruation, but many women find it very difficult to achieve and sustain significant weight loss. A scientific review in 2013 found similar decreases in weight and body composition and improvements in pregnancy rate, menstrual regularity, ovulation, hyperandrogenism, insulin resistance, lipids, and quality of life to occur with weight loss independent of diet composition. Still, a low GI diet, in which a significant part of total carbohydrates are obtained from fruit, vegetables, and whole-grain sources, has resulted in greater menstrual regularity than a macronutrient-matched healthy diet.

Vitamin D deficiency may play some role in the development of the metabolic syndrome, so treatment of any such deficiency is indicated. However, a systematic review of 2015 found no evidence that vitamin D supplementation reduced or mitigated metabolic and hormonal dysregulations in PCOS. As of 2012, interventions using dietary supplements to correct metabolic deficiencies in people with PCOS had been tested in small, uncontrolled and nonrandomized clinical trials; the resulting data is insufficient to recommend their use.

Medications for PCOS include oral contraceptives and metformin. The oral contraceptives increase sex hormone binding globulin production, which increases binding of free testosterone. This reduces the symptoms of hirsutism caused by high testosterone and regulates return to normal menstrual periods. Metformin is a drug commonly used in type 2 diabetes to reduce insulin resistance, and is used off label (in the UK, US, AU and EU) to treat insulin resistance seen in PCOS. In many cases, metformin also supports ovarian function and return to normal ovulation. Spironolactone can be used for its antiandrogenic effects, and the topical cream eflornithine can be used to reduce facial hair. A newer insulin resistance drug class, the thiazolidinediones (glitazones), have shown equivalent efficacy to metformin, but metformin has a more favorable side effect profile. The United Kingdom's National Institute for Health and Clinical Excellence recommended in 2004 that women with PCOS and a body mass index above 25 be given metformin when other therapy has failed to produce results. Metformin may not be effective in every type of PCOS, and therefore there is some disagreement about whether it should be used as a general first line therapy. The use of statins in the management of underlying metabolic syndrome remains unclear.

It can be difficult to become pregnant with PCOS because it causes irregular ovulation. Medications to induce fertility when trying to conceive include the ovulation inducer clomiphene or pulsatile leuprolide. Metformin improves the efficacy of fertility treatment when used in combination with clomiphene. Metformin is thought to be safe to use during pregnancy (pregnancy category B in the US). A review in 2014 concluded that the use of metformin does not increase the risk of major birth defects in women treated with metformin during the first trimester.

In order to determine the relative prevalence of different fetishes, scientists obtained a sample of at least 5000 individuals worldwide, in 2007, from 381 Internet discussion groups. The relative prevalences were estimated based on (a) the number of groups devoted to a particular fetish, (b) the number of individuals participating in the groups and (c) the number of messages exchanged. Of the sampled population, 7 percent were sexually aroused by hair (as opposed to 12 for underwear, but only 4 for genitals, 3 for breasts, 2 for buttocks, and less than one for body hair).

5α-Reductase is an enzyme that converts testosterone to 5α-dihydrotestosterone (DHT) in peripheral tissues. These enzymes also participate in the creation of such neurosteroids as allopregnanolone and THDOC, convert progesterone into dihydroprogesterone (DHP), and convert deoxycorticosterone (DOC) into dihydrodeoxycorticosterone (DHDOC). 5-ARD is biochemically characterized by low to low-normal levels of testosterone and decreased levels of DHT, creating a higher testosterone/DHT ratio.

DHT is a potent androgen, and is necessary for the development of male external genitalia in utero.

GH deficiency is treated by replacing GH with daily injections under the skin or into muscle. Until 1985, growth hormone for treatment was obtained by extraction from human pituitary glands collected at autopsy. Since 1985, recombinant human growth hormone (rHGH) is a recombinant form of human GH produced by genetically engineered bacteria, manufactured by recombinant DNA technology. In both children and adults, costs of treatment in terms of money, effort, and the impact on day-to-day life, are substantial.

GH treatment is not recommended for children who are not growing despite having normal levels of growth hormone, and in the UK it is not licensed for this use. Children requiring treatment usually receive daily injections of growth hormone. Most pediatric endocrinologists monitor growth and adjust dose every 3–6 months and many of these visits involve blood tests and x-rays. Treatment is usually extended as long as the child is growing, and lifelong continuation may be recommended for those most severely deficient. Nearly painless insulin syringes, pen injectors, or a needle-free delivery system reduce the discomfort. Injection sites include the biceps, thigh, buttocks, and stomach. Injection sites should be rotated daily to avoid lipoatrophy. Treatment is expensive, costing as much as US $10,000 to $40,000 a year in the USA.

The condition affects only those with a Y-chromosome because dihydrotestosterone (DHT) has no known role in development of XX fetuses.

Guttate psoriasis accounts for approximately 2% of psoriasis cases.

The treatments used for plaque psoriasis can also be used for guttate psoriasis. Few studies have specifically focused on guttate psoriasis management, so there is currently no firm guidelines for managing guttate psoriasis differently from plaque psoriasis. Due to the role streptococcal infection plays in the development of guttate psoriasis, systemic antibiotics have been considered as a potential treatment option. Although systemic antibiotics may be considered to treat the initial infection at its source, there is no support for their use in the management of subsequent guttate psoriasis itself. The condition often usually clears up on its own within weeks to months, and only about one third of patients will develop chronic plaques.