Hair Loss On One Side of Head – Causes & Treatments

  • Medically reviewed by: Debra Rose Wilson, PhD MSN RN IBCLC AHN-BC CHT
  • Written by: William Slator
  • Last updated: 26/02/2024

This article will address one-sided hair loss. This will include a look at:

  • what it is
  • its most common causes
  • how to distinguish between them
  • steps you can take to combat it and regrow your hair

What Is One-Sided Hair Loss?

One-sided hair loss is thinning and hair loss that occurs on one side of the scalp. The hair loss can be completely or predominantly on one side. It can occur in discrete patches, or more diffusely over larger areas of the head. Either way, the result is an asymmetrical appearance of the hair.

While not very common, one-sided hair loss can happen for a number of reasons. Even in individuals with Androgenetic Alopecia (AGA), the recession may occur more quickly on one side than the other (known as an uneven hairline). However, true one-sided alopecia is usually caused by different conditions.

What Causes This Uneven Hair Loss?

Here are a few causes of uneven hair loss.

Alopecia Areata

Alopecia Areata (AA) is an autoimmune disorder that leads to patchy, nonscarring hair loss. The tell-tale sign of alopecia areata is clearly defined patches of completely bald scalp, surrounded by more or less intact hair (1). The clearest difference compared to male or female pattern baldness is the pattern of progression. While baldness progresses in a predictable fashion, alopecia areata can strike at any part of the head.

Alopecia areata

The bald patches can appear literally anywhere. This includes parts of the scalp that are immune to regular baldness, like the sides and back of the head. They can also appear on other parts of the body, like the beard, eyelashes, eyebrows, or bodily hair. Because of its random nature, alopecia areata of the scalp will almost always lead to asymmetrical hair loss.

The causes are not fully understood, but there is almost certainly a strong autoimmune component (2). T cells are white blood cells that form part of the immune system. They play a critical role in attacking pathogens like viruses. But for reasons that are still unknown, in alopecia areata, these T cells infiltrate the hair follicles and lead to hair loss (3).

While AA is often reversible if caught early, in its chronic version it can lead to follicle miniaturization and permanent hair loss. In this respect, it is similar to pattern baldness. Alopecia areata is often associated with thyroid problems and your doctor needs to do blood tests and make recommendations (4).

In addition to the patchy form of AA, which is by far the most common, there are cases with total balding of the scalp and face (alopecia totalis) as well as total body hair loss (alopecia universalis).


An impulse control disorder that leads to the pulling out of one’s own hair, trichotillomania is a common cause of patchy hair loss (5). Individuals with trichotillomania may pull hair from their scalp, eyelashes, or eyebrows. They can also pull hair from other parts of the body like the arms, legs, or chest.

The impulse to pull one’s hair is purely psychological in nature. There is no underlying pain or discomfort, and the roots of the impulse will often be a mystery to the patients themselves.

Sometimes the hair pulling is done unconsciously, without the patient even realizing it, but other times it is the result of conscious and very focused plucking (6). The condition is more common in girls and women, though men can also be affected.

There are treatment options for individuals suffering from this disorder (including therapy and medication). If the hair pulling has gone on for an extended period of time, the hair follicles may be permanently damaged, and the hair might not grow back fully.


Sometimes, uneven hair loss can be caused by traction on one side of the head. This is typically the result of hairstyles like braids and extensions. It can also be the result of sleeping on the same side for many years.

Trauma or Illness

From head injuries to stroke, there are a number of injuries and illnesses that can trigger asymmetrical hair loss. Scarring and poor blood flow to a particular location of the scalp are two of the common causes of injury- and illness-related hair loss. Depending on location, these can lead to asymmetrical hair loss.

Dandruff and Seborrheic Dermatitis

Dandruff is a very common condition, affecting as much as one-half of the general population (7).

We all lose skin cells on our scalp all the time as a result of the natural cell lifecycle. In dandruff, however, these cells retain a high degree of cohesion and fall off in large chunks. These are the white flakes that are the hallmark of the condition.

Closeup of dandruff flakes

Seborrheic dermatitis is a related condition that is generally milder than dandruff and can appear in areas outside the scalp, like the face and chest (8).

Neither of these conditions leads to alopecia in and of themselves. Over time, the constant itching and inflammation associated with them can certainly lead to hair thinning and balding. If these symptoms are more prevalent on one particular area of the scalp, this could potentially lead to uneven hair thinning.

Other causes

Though far rarer than the aforementioned, another possible cause of one-sided hair loss can be a fungal infection. This can lead to patchy and seemingly random bald patches.

The most common fungal infection causing hair loss in the scalp is tinea capitis, commonly – and incorrectly – referred to as scalp ringworm (9).

Finally, a rare inflammatory condition known as lichen planus can affect the scalp in an asymmetrical pattern, leading to irreversible hair loss in the affected areas (10).

How to Treat One-Sided Hair Loss

With a better understanding of the most common causes, it is now time to learn how to treat the underlying issue so you can regrow your hair.

1. Find the Cause

As shown above, there are a few conditions or circumstances that can lead to one-sided hair loss. In order to properly treat the issue, you need to narrow down the cause. In some cases, the cause can be easy to determine. However, you may also require the help of a dermatologist.

2. Treat the Issue at Its Source

After you have identified the cause of the one-sided hair loss, the next step is to take the appropriate action.

Ginseng is a natural treatment for alopecia areata.

For alopecia areata, there is currently no FDA-approved medical treatment. Many doctors prescribe minoxidil off-label, with mixed results. There are also a number of natural treatments you can try. Onion juice is one such treatment, as is ginseng.

The most effective treatment for trichotillomania is behavioral therapy, but this may be a costly and not easily accessible option for some people. Another treatment option is pharmacotherapy with antidepressants, though you will need to work with your doctor or a psychiatrist.

For chronic dandruff, there are many over-the-counter medications and shampoos. Most of them, like ketoconazole, are available without a prescription. There are also various practical steps you can take, such as avoiding the excessive use of hair styling products and getting moderate sun exposure.

In the rare event that your one-sided hair loss is due to a rare condition like tinea capitis or lichen planus, a dermatologist will prescribe the best course of treatment.

3. Support Your Hair’s Overall Health

Once you have identified the specific cause of your one-sided hair loss and have taken appropriate action, the next step is to support the health of your hair and encourage growth on a more fundamental level. There are a number of ways to do this.

4. Cosmetic Interventions

Sometimes it will not be possible to completely reverse uneven hair loss, even if you have identified the cause. In this case, you can consider cosmetic interventions that will mask hair loss.

Scalp micropigmentation is a non-surgical, non-invasive cosmetic treatment that involves the application of micro-needles to deposit pigment onto the scalp. The method is designed to mimic the appearance of hair stubble and create the illusion of thicker hair.

Though sometimes called a hair tattoo, this procedure does have differences compared to a regular tattoo. The most obvious difference is the training and skills of the practitioner carrying out the procedure. The needles utilized are also different from those used in a regular tattoo, as is the depth of the pigmentation, which is slightly shallower compared to a regular tattoo.

At the hands of a competent practitioner, scalp micropigmentation can give very good results, and restore the appearance of a full head of hair.

Scalp Massage and Stimulation

This is a great treatment option for everyone, whether they suffer from hair loss or not. Head massagers can improve your scalp massaging efforts and stimulate hair growth.

Blood flow is important in the hair growth process. This is because blood not only delivers oxygen and vital nutrients to the hair follicles, but also removes waste and harmful buildup.

For a long time, the usefulness of scalp massages was met with skepticism, but the times are now changing.

A recent study out of Japan found that scalp massages in healthy men resulted in increased hair thickness after 24 weeks (11). The study also found that the mechanical stimulation provided by the scalp massages resulted in increased expression of hair cycle genes and decreased expressions of genes implicated in hair loss.

Not only is the scalp massage a highly effective way of promoting healthy hair, but it is also an easy and low-cost intervention.

A man performing a scalp massage on his hairline

To begin, use your fingertips to massage your scalp (paying particular attention to the affected area) for at least 5 minutes each day. You can also use a scalp massager or dermaroller to really get the blood pumping.

Reduce Stress & Remove Hair Loss Triggers

Stress is a common factor in various types of hair loss, like alopecia areata, and is possibly also an aggravating factor in individuals with trichotillomania. There are a number of stress reduction techniques that you can do easily at home. These include Qi breathing, meditation, yoga, and self-massage.

Meditation can be effective in relieving stress.

Of course, you can also utilize the services of a professional, such as a massage therapist or counselor.

In addition to reducing stress, you will also want to eliminate stressful triggers from your life.


No matter the cause, you do not have to suffer from the effects of irregular thinning and balding. While uneven hair loss can be frustrating, it will usually be treatable through various options.

The challenge is identifying the underlying cause. In this article, we have outlined most causes and suggested the most appropriate treatments. In addition to these targeted treatments, there are a number of other interventions that will promote healthy hair in all people, whether they are suffering from one-sided hair loss or not.

Information contained on this website has not been evaluated by any medical body such as the Food & Drug Administration. All information is for educational purposes only. We do not aim to diagnose, treat, cure or prevent any disease or illness. You must consult a medical professional before acting on any content on this website.