Alopecia: what is it, types, causes, treatment

Mike Bohl, MD, MPH, ALM - Contributor Avatar

Written by Chimene Richa, MD 

Mike Bohl, MD, MPH, ALM - Contributor Avatar

Written by Chimene Richa, MD 

last updated: Jun 04, 2021

6 min read

Losing hair is a normal part of life—but that doesn’t mean that you have to be happy about it. Alopecia is the medical term for hair loss, but you may not realize there are several different hair loss types. Each has its own causes and treatments. Read on to learn more.

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What is alopecia?

Alopecia is the medical term for hair loss. Everyone loses about 50–100 hairs a day as part of the normal hair growth cycle (Murphrey, 2019). However, if your hair is thinning or you are starting to notice bald patches (areas where hair no longer grows), you may have alopecia. Alopecia usually affects your scalp but can affect hair on other parts of your body, such as eyebrows and eyelashes. 

Depending on the cause, alopecia may be reversible. Hair loss, while not dangerous, can be distressing for both men and women. Discuss your medical history and any medications you are taking with your healthcare provider, especially before trying any alopecia treatments. 

Symptoms of alopecia

Men and women show hair loss differently. In men, alopecia looks like thinning on the top of the head or the sides of the scalp; they can also have hair loss at the hairline (receding hairline). Women typically see thinning on the tops of their heads or throughout their hair; the first sign is often a widening part. Women generally do not get a receding hairline (Phillips, 2017). 

What causes alopecia?

Many factors can cause alopecia, including genetics, illness, stress, diet, medications, childbirth, and certain hair care habits.

Hereditary hair loss that occurs with aging is the most common cause of alopecia, but others include (Phillips, 2017):

  • Autoimmune disease—Sometimes, the immune system attacks the body, or in this case, its hair follicles (hair-producing cells); this leads to a condition known as alopecia areata.

  • Medical conditions—These include thyroid disease and anemia, among others.

  • Chronic illness—Major surgery, high fevers, severe infection, etc. can lead to temporary hair loss, also known as telogen effluvium.

  • Cancer treatments like radiation and chemotherapy can cause hair loss. 

  • Scalp ringworm—This is usually seen in children and is a fungal infection that can lead to hair loss and eventually balding if not treated appropriately. 

  • Mental disorder—Trichotillomania is a condition where a person pulls out the hair on their scalp, eyebrows, and eyelashes. 

  • Hormonal changes—Childbirth, menopause, and stress can all cause alopecia.

  • Nutrition issues—Weight loss, eating disorders, too much vitamin A, too little iron (anemia), and too little protein in your diet can all cause hair loss.

  • Prescription medications—Certain medications can lead to hair loss in some people; these include birth control pills, blood thinners, retinoids, as well as drugs used to treat arthritis, depression, gout, high blood pressure, and heart problems

  • Haircare—excessive use of high heat on hair, chemicals in hair products, and long-term use of styles that pull or tug on hair can lead to alopecia. 

Types of alopecia

There are quite a few types of alopecia. 

Androgenic alopecia

Also known as hereditary thinning or baldness, androgenic alopecia is the most common type of alopecia (Al Aboud, 2020). It causes the typical “male pattern baldness" or “female pattern baldness." It's genetic, and many people have a family member who also has the condition. 

Androgenic alopecia is seen most often in white men. Its prevalence varies with age—30% experience it at age 30, 40% at age 40, and 50% at age 50. This type of alopecia is less common in women, affecting about 38% of women over 70 (Phillips, 2017). 

Alopecia areata

This type of alopecia is an autoimmune condition where the body attacks its own hair, leading to one of three different types of baldness patterns (Lepe, 2020):

  • Alopecia areata patchy—round patches of hair loss on the scalp and other places on the body

  • Alopecia totalis—total loss of hair on the scalp

  • Alopecia universalis—complete loss of all body hair

It is not clear what triggers a person’s immune system to attack their hair follicles; most likely, it’s caused by a combination of genetic and environmental factors. According to the National Alopecia Areata Foundation (NAAF), one theory is that people who have the genes for alopecia areata get exposed to something that triggers the disease, leading to hair loss. Unfortunately, these triggers are not well understood (NAAF, n.d.). 

Alopecia areata can get better on its own or with treatment; it comes and goes in an unpredictable pattern, which can be frustrating for people with this condition. Alopecia areata is associated with other autoimmune diseases like thyroid disease, celiac disease, rheumatoid arthritis, vitiligo, and type 1 diabetes, though most people with alopecia areata are otherwise healthy (Jabbari, 2013).

Cicatricial alopecia

Cicatricial, or scarring, alopecia occurs because inflammation kills the hair follicles and replaces them with scar tissue. Scar tissue cannot grow hair, and the result is a bald spot. Several skin disorders can cause this, including folliculitis (inflammation of the hair follicles) and lupus (Phillips, 2017). 

Telogen effluvium

Sometimes an illness or a medication you are taking can disrupt the hair growth cycle. When this happens, too many hairs enter the resting (telogen) phase and then fall out at the same time a few months later. 

Telogen effluvium can result from several conditions like a severe chronic illness, pregnancy, surgery, severe infection, or endocrine (hormone) problems. This type of hair loss is sometimes a side effect of certain medications like those for treating acne, seizures, thyroid problems, and blood pressure, among others. If you have this problem, you may notice your hair coming out in clumps several months after the illness or medication use. Fortunately, once you address the underlying cause, the hair usually regrows (Phillips, 2017).

Tinea capitis

Tinea capitis is caused by a contagious fungal infection that you can get from contaminated hats, brushes, etc. The infection gets into the hair follicles and leads to itching and hair loss; it can cause balding if left untreated. Tinea capitis mainly affects children (Phillips, 2017).

Traction alopecia

Wearing hairstyles that pull on the hair can lead to hair loss over time, called traction alopecia. This condition is more prevalent in African American women; hairstyles that can cause this include braiding, tight ponytails, etc. Treatment involves stopping the use of high-tension hairstyles (Billero, 2018).


Trichotillomania is an impulse-control disorder where you cannot stop pulling your hair. Usually, people pull the hair from their scalp, but sometimes they go after the hair in their eyebrows, eyelashes, or other places on their body. The hairs in the thinning patches often look broken.  Treatment usually involves a combination of medication and therapy. Trichotillomania affects 4% of Americans, often children and teenagers (Phillips, 2017).

How to treat alopecia

Since there are various causes and types of alopecia, treatment options vary. Your healthcare provider or dermatologist may need to perform additional tests on your hair or scalp to find out the cause of your hair loss. Determining the reason behind your alopecia will help guide your treatment plan. 

Many treatments exist, and your provider can help you identify which ones are right for you—some people end up needing a combination of treatments. Both over-the-counter and prescription medications are available to help with alopecia, including (Donovan, 2021): 

  • Minoxidil (brand name Rogaine)—This is an over-the-counter treatment that is FDA approved for androgenic alopecia in both men and women to decrease hair loss and stimulate hair regrowth; it is applied directly to the scalp.

  • Finasteride (brand name Propecia; see —This is a prescription medication that is FDA approved to help slow hair loss and stimulate hair regrowth in men with androgenic alopecia. It works by halting a man’s production of dihydrotestosterone (DHT), a male hormone. Women who are pregnant should not touch any broken tablets.

  • Immunosuppressants—If inflammation is one of the causes of your alopecia, your provider may recommend the use of immunotherapy medications to decrease the body’s ability to attack its own hair follicles. This class of drugs includes corticosteroids, methotrexate, sulfasalazine, and cyclosporine (Lepe, 2020).

  • Scalp sensitizers—These medications stimulate a particular type of inflammation of the skin (dermatitis) of the scalp to redirect the body’s immune system; this group includes anthralin and diphencyprone (DPCP) (Spano, 2015).

In addition to medical treatments, there are procedures to help restore hair. Hair transplantation is one option; this is where scalp skin that still has good hair growth is transplanted to balding areas of the scalp. There is also an FDA-cleared low-level laser device that might improve hair growth in some people (Donovan, 2021). 

Lastly, non-medical options like wigs, hairpieces, scarves, shaving, etc., can be used to camouflage hair loss. Seek medical advice from your provider to see which hair loss treatment options are right for you.

How to prevent alopecia

Some causes of alopecia may be beyond your control: genetics, autoimmune disease, illness, etc. However, there are things you can do to try to prevent hair loss: 

  • Avoid harsh chemicals and bleaching as they can damage hair follicles and may lead to hair loss (Bloch, 2019). 

  • Steer clear of hairstyles that involve tight braids to prevent potential traction alopecia.

  • Eat a healthy, balanced diet rich in protein, fruits, and vegetables.

  • Avoid over-brushing your hair.

  • Stop using high heat on your hair as this dries out and damages follicles.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

June 04, 2021

Written by

Chimene Richa, MD

Fact checked by

Mike Bohl, MD, MPH, ALM

About the medical reviewer

Dr. Mike is a licensed physician and a former Director, Medical Content & Education at Ro.