Telogen Effluvium

When significantly more than 10% of the scalp hair follicles are in the telogen growth phase, this will manifest in certain patients as a rather dramatic hair-shedding event. Effluvium simply refers to the shedding of excess matter (in this case, hair).

Telogen effluvium most often will resolve on its own and will not result in permanent hair loss. Severe illness (for example, COVID-19 or surgery), pregnancy, dietary triggers, and emotional trauma can cause telogen effluvium. One must distinguish this form of hair loss from other conditions affecting the scalp.

For the sake of discussion, the human hair cycle has been divided into three segments:

• Anagen (the growth portion which can last for as long as 5 years and generally involves about 90% of the hair)
• Catagen (can last for 6 weeks during which the hair follicles become atrophic)
• Telogen phase (involves about 10% of the hairs, can last for 6 months during which a club hair is formed and the hair is shed)

When significantly more than 10% of the scalp hair is in the telogen phase, it can manifest as significant hair shedding.

There are many factors that are thought to influence the movement of hair follicles into the catagen and then telogen phases, such as:

• Drugs
• Pregnancy
• Medications
• Severe illnesses
• Emotional distress
• Dietary triggers

Since all the follicles in the scalp will be involved in the telogen portion of the natural hair cycle, it stands to reason that symptomatic disease will only be manifest in those individuals with a significant amount of hair. So, it is unlikely that anyone with pattern alopecia (androgenetic balding) would notice or complain of telogen effluvium.

Pregnancy is a well-recognized risk factor.

Certain drugs have been associated with this condition, which includes:

• Oral contraceptive pills
• Androgens
• Retinoids
• Beta-blockers
• ACE (angiotensin-converting enzyme) inhibitors
• Anticonvulsants
• Antidepressants
• Anticoagulants (heparin)

The major sign of course is the shedding of an abnormal amount of hair. One way to assess this is to avoid shampooing for 4-5 days and then shampoo and collect and count all the hairs that one finds in the sink before disposing of them down the drain. If there are more than 100 hairs, this is compatible with telogen effluvium.

Although rare, some patients may complain of hair pain or tenderness in the areas where they are losing hair.

Most of the time, telogen effluvium is a diagnosis of exclusion, meaning that other causes for hair shedding need to be considered. By definition, telogen effluvium produces no change in the skin of the scalp.

Other types of non-scarring hair loss like androgenetic alopecia, alopecia areata, and secondary syphilis are relatively easy to distinguish due to their characteristic pattern.

Assuming there are greater than 100 hairs shed over the previous 5 days, one can do a hair pull and examine the morphology of the follicular root. If a majority of follicles show club hairs (final hair growth that features a bulb of keratin at the root tip), which is the way hairs in telogen look, then this supports the diagnosis of telogen effluvium.

Most patients with diffuse hair loss should have a complete blood count, thyroid function assays, and perhaps a serum iron level. Rarely, a biopsy of the scalp skin or more extensive laboratory work will be necessary to support the diagnosis.

Since telogen effluvium is self-limited frequently, reassurance will be sufficient and the patient will need to be seen back within a few months to ensure that hair growth has returned to normal. If there is evidence of a drug etiology, then some pharmaceutical substitution should be made. Any systemic disease needs to be controlled if there is a suspicion that it might be involved in this condition.

A good well-rounded diet is necessary for normal hair growth, and vitamin and or/mineral supplementation may need to be considered.

Occasionally, patients are treated with over-the-counter (OTC) topical minoxidil with some modest success, but this should be confined to use in those with a chronic course of longer than a few months.

Aside from a well-balanced diet sufficiently high in protein, there is little one can do at home to affect the course of the condition.

The prognosis for telogen effluvium is excellent because the normal hair cycle generally will take over within a few months.

There is little one can do to prevent telogen effluvium.