Hair Loss : Types, Cause, Prevention, Treatment

Hair loss is not life threatening, but it is distressing and significantly affects the patient’s quality of life. Hair loss can range from mild hair thinning to total baldness. Hair can fall out for many different reasons.

Types of Hair Loss

There are several categories of hair loss, including:

• Telogen effluvium — This common form of hair loss happens two to three months after a major body stress, such as a prolonged illness, major surgery or serious infection. It also can happen after a sudden change in hormone levels, especially in women after childbirth. Moderate amounts of hair fall out from all parts of the scalp, and may be noticed on a pillow, in the tub or on a hairbrush. While hair on some parts of the scalp may appear thinner, it is rare to see large bald spots.
• Drug side effects — Hair loss can be a side effect of certain medications, including lithium, beta-blockers, warfarin, heparin, amphetamines and levodopa.  In addition, many medications used in cancer chemotherapy — such as doxorubicin (Adriamycin) — commonly cause sudden hair loss affecting the entire head.
• Symptom of a medical illness — Hair loss can be one of the symptoms of a medical illness, such as systemic lupus erythematosus (lupus), syphilis, a thyroid disorder (e.g. hypothyroidism or hyperthyroidism), a sex-hormone imbalance or a serious nutritional problem, especially a deficiency of protein, iron, zinc or biotin. T
• Tinea capitis (fungal infection of the scalp) — This form of patchy hair loss happens when certain types of fungi infect the scalp. This causes the hair to break off at the scalp surface and the scalp to flake or become scaly. 
• Alopecia areata — This is an autoimmune disease that causes hair to fall out in one or more small patches. The cause of this condition is unknown, although it is more common in people who have other autoimmune diseases. Total loss of hair from the scalp with the same process, it is known as alopecia totalis.
• Traumatic alopecia — This form of hair loss is caused by hairdressing techniques that pull the hair (tight braiding or cornrowing), expose hair to extreme heat and twisting (curling iron or hot rollers) or damage the hair with strong chemicals (bleaching, hair coloring, permanent waves). It can also happen in some people  who have an uncommon psychiatric disorder (trichotillomania) in which compulsive hair pulling and twisting can cause bald spots.
• Hereditary pattern baldness, or androgenetic alopecia — In men, hair loss may follow the typical male pattern (receding front hairline and/or thinning hair at the top of the head). This is the most common type of hair loss, and it can begin at any time in a man's life, even during his teen years. It usually is caused by the interaction of three factors: an inherited tendency toward baldness, male hormones and increasing age. Many women will develop some degree of female-pattern baldness. In women, thinning occurs over the entire top or crown of the scalp, sparing the front of the scalp.

Difference male vs female pattern hair loss

Male Pattern Baldness

Female Pattern Baldness

Duration of hair loss lasts depends on the cause. 

• In telogen effluvium, hair usually is lost over several weeks to months, but then grows back over the next several months. 
• If hair loss caused by side effect of a medication, hair growth usually returns to normal once the drug is stopped. 
• When the cause is abusive hairdressing, the hair loss usually stops after you change to more natural styling, except in traction alopecia, which results from years of pulling the hair back in tight braids. 
• In tinea scalp infection, the fungus must be treated for at least 6 to 12 weeks and hair regrowth may be slow.

Early treatment is very important in preventing possible permanent hair loss. Both male- and female-pattern baldness tend to get worse over time but can be treated.

Can we prevent hair loss ?

Some forms of hair loss can be prevented by 

• minimizing stress
• eating a healthy diet
• using sensible hairdressing techniques,
• if possible, switching to medications that do not cause hair loss. 
• keeping hair clean and by never sharing hats, combs or brushes with other people ( fungal infection)
• For hereditary-pattern baldness can sometimes be prevented by medication.

Treatment

Call your doctor whenever you are concerned about hair loss, especially if you are having other unexplained symptoms. Your doctor will identify the cause and give the spesific treatment to treat hair loss. 

Hair loss resulting from telogen effluvium or drug side effects usually requires no treatment other than discontinuing the medication that is causing the problem. 

Limiting trauma or chemical exposure (such as use of a blow dryer, hair straightener, coloring or perms) may limit or stop hair loss. 

Hair loss from poor nutrition or medical illness usually stops with the adoption of a healthy diet and treatment of the underlying medical condition. 

Treatment of fungal scalp infection requires 6 to 12 weeks of oral medication, such as terbinafine or itraconazole, with or without shampoos containing selenium sulfide or ketoconazole. 

Alopecia areata can be treated with a corticosteroid that is injected or applied to the skin. Other treatments for this condition include anthralin cream, minoxidil  or a combination of these therapies.

Many men and women with hereditary-pattern baldness do not seek treatment for hair loss. For those who do seek medical treatment, initial therapy is usually topical minoxidil . Men can also be treated with oral finasteride  or dutasteride  or they can choose hair transplants or scalp-reduction surgery. 

Premenopausal women may be treated with estrogen or spironolactone while finasteride may be recommended for postmenopausal women.

Reference :

www.health.harvard.edu/a_to_z/hair-loss-a-to-z

www.aafp.org/afp/2017/0915/p371.html