Hair loss can occur as thinning hair or complete baldness. The hair loss may be on the head or any other part of the body that normally has hair, such as the eyebrows.
What is going on in the body?
There are many causes of hair loss. The most common form of hair loss is due to
male pattern baldness, in which hair is lost from the front and top of the scalp. Other types of hair loss can create different patterns. Treatment depends on the type and cause of baldness.
What are the causes and risks of the condition?
Hair loss can be due to:
male pattern baldness, the most common type of hair loss, which is usually inherited from one of the parents
inflammation of the scalp, which can cause patchy hair loss and is often treatable
medications, such as chemotherapy
radiation therapy of the head, usually to treat cancer
infections, such as a fungal infection of the scalp or a sexually transmitted infection called syphilis
- trauma to the hair or scalp, which may include certain hairstyles that constantly pull on the hair, such as tight braids
Certain diseases can also cause the condition:
low levels of iron in the body, which may also cause anemia, or a low red blood cell count
hypothyroidism, which is a condition caused by low levels of thyroid hormones
systemic lupus erythematosus, a bodywide disease that attacks many organ systems
an obsessive-compulsive disorder known as trichophilomania
- very rarely, cancer
Female pattern baldness usually causes thinning of the hair on the top and sides of the head. Some causes of female pattern baldness are:
- stress, including emotional stress, surgery, illness, or rapid weight change
- hormonal changes, including those caused by pregnancy, menopause, or use of oral contraceptives
- hormonal imbalances, such as hypothyroidism, which is a low level of thyroid hormone
- some medications, such as those used for gout and high blood pressure
- high levels of vitamin A
What can be done to prevent the condition?
There are medications available to prevent hair loss in men with a strong family history of the common type of baldness. Early treatment of fungal infections and syphilis
can prevent some cases of hair loss. Early correction of low iron
levels or hypothyroidism
may also prevent some cases. Many cases cannot be prevented but may respond to treatment.
How is the condition diagnosed?
The affected person usually notices the hair loss. A medical history and physical exam often make the healthcare provider suspect a certain cause. Some methods used to diagnose the cause of hair loss include:
- scraping the affected area to collect hairs. The hairs can be examined with a microscope or analyzed by a lab to look for certain causes of hair loss.
of the skin. A biopsy involves taking a small piece of skin with a special tool and sending it to the lab for testing.
- blood tests to check for certain diseases
Long Term Effects
What are the long-term effects of the condition?
If not treated, hair loss can worsen. With male pattern baldness, this is the only long-term effect. Scarring of the skin can occur with certain causes of hair loss. Other long-term effects may occur, but they depend on the cause of the hair loss.
What are the risks to others?
Many cases of hair loss in children are due to fungal infections. These are fairly contagious and can be spread by close contact with other children or sharing combs or hairbrushes.
Syphilis, a sexually transmitted disease, is a rare cause of hair loss. Other forms of hair loss, which make up the majority of cases, are not contagious.
What are the treatments for the condition?
Treatment is directed at the underlying cause. Treatment may include:
medication for male pattern baldness, such as minoxidil (i.e., Rogaine) and finasteride (i.e., Propecia)
antibiotics to treat a fungal or syphilis infection
stopping a medication that is causing hair loss
medication to treat an underlying condition, such as iron or thyroid hormone pills
- medications applied to the area of hair loss to reduce inflammation
Some people may choose hair grafting, or hair transplantation, to cover areas of hair loss. There are several hair-grafting techniques, which involve taking pieces of scalp from hair-growing areas on the back or side of the head and placing them into slits on the balding areas.
Wigs, hair weaves, toupees, and other hairpieces may be used to cover areas where hair is thin or absent. Other treatments may be used for other causes. Some people choose no treatment at all.
What are the side effects of the treatments?
All medications may cause side effects. For example, finasteride (i.e., Propecia) may cause erectile dysfunction in men. Antibiotics may cause rash, stomach upset, or allergic reactions.
What happens after treatment for the condition?
If treatment is successful, the hair loss stops. With male pattern baldness, treatment is often needed for life to prevent further hair loss. In some cases, treatment may allow the hair to grow back completely. Treatment may be needed for long periods of time if the underlying cause is a serious disease.
How is the condition monitored?
Both the affected person and the healthcare provider can frequently examine the area of hair loss to see if treatment is effective. Other monitoring depends on the cause of the hair loss. Any new or worsening symptoms should be reported to the healthcare provider.
Conn's Current Therapy, 1999, Rakel et al.