Patient Basics: Telogen Effluvium

Telogen effluvium is a common type of temporary hair shedding. It starts about two to three months after a shock to the body, such as a high fever, surgery, childbirth or severe stress, and hair falls out evenly from all over the scalp. It can be alarming, but the hair roots stay healthy, and the hair grows back once the trigger has passed.

Key points

• The shedding usually starts 2 to 3 months after the trigger, so people often don’t connect the two.
• Common triggers are illness with fever, giving birth, surgery, crash diets, low iron, thyroid problems and some medicines.
• It causes overall thinning, not bald patches.
• Shedding usually stops within about six months, and hair regrows over the following months.
• A doctor can check for causes that need treatment, such as low iron or a thyroid problem.

How hair grows and sheds

Each hair goes through a cycle. Most of the hairs on your head, about 9 in 10, are in a long growing phase that lasts years. The rest are in a resting phase, called telogen, which lasts about three months. Then the resting hair falls out and a new hair starts growing in the same follicle. Losing about 50 to 100 hairs a day is normal.

A big physical or emotional shock can push many growing hairs into the resting phase at the same time. About three months later, they all fall out together. That wave of shedding is telogen effluvium.

What causes telogen effluvium

• Illness. A high fever, flu, COVID-19 or another serious infection
• Childbirth. Shedding after pregnancy often peaks 3 to 4 months after the baby is born.
• Surgery or a major injury
• Severe emotional stress, such as a death in the family or a divorce
• Rapid weight loss from crash dieting, weight-loss medicines or weight-loss surgery, or eating too little protein
• Low iron or other nutrient shortages
• Thyroid disease, either an underactive or an overactive thyroid
• Hormone changes, such as stopping birth control pills
• Medicines, including some blood thinners, beta-blockers, retinoids such as isotretinoin, seizure medicines and lithium. Starting minoxidil can also cause a short burst of shedding.

Sometimes no trigger is found. When shedding goes on for more than six months, doctors call it chronic telogen effluvium. It is most common in women aged 30 to 60, and it can come and go for years without leading to baldness.

Symptoms

• Much more hair than usual in your brush, the shower drain or on your pillow
• Hair that comes out easily when you run your fingers through it
• A ponytail that feels thinner
• Thinning all over the scalp, sometimes most noticeable at the temples

Shed hairs often have a tiny white bulb at the root. That’s a normal resting hair, not a sign that the root is damaged. The scalp itself usually looks healthy, without redness, scaling or bald spots.

How telogen effluvium is diagnosed

A doctor or dermatologist (skin and hair specialist) will ask about your health over the past six months, including illness, pregnancy, surgery, stress, diet and new medicines. They will look at your scalp and may do a gentle pull test, tugging lightly on a small group of hairs to see how many come out. They may also look at the scalp with a magnifier.

Blood tests often include:

• A blood count and ferritin, to check for anemia and low iron stores
• Thyroid tests
• Sometimes vitamin D, zinc or other tests based on your history

A small scalp biopsy is rarely needed. It may help if the doctor can’t tell telogen effluvium apart from pattern hair loss or another hair condition.

Treatment

Telogen effluvium usually stops on its own once the trigger is over. Most people need no treatment beyond time. These steps help:

• Treat the cause. This might mean iron pills for low iron, treatment for a thyroid problem, or a different medicine if one is to blame. Don’t stop a medicine without talking to your doctor.
• Eat enough. Include protein at each meal, and avoid crash diets.
• Be gentle with your hair. Normal washing and brushing won’t make you lose more hair. Do skip tight ponytails, braids and harsh treatments such as bleaching or perms while it grows back.
• Consider minoxidil. For chronic shedding, a dermatologist may suggest minoxidil foam or solution, or minoxidil pills, to help hair grow.

A shorter or layered haircut and volumizing products can make thinning less noticeable while you wait.

Common questions about telogen effluvium

How long does telogen effluvium last?

Shedding usually lasts about three to six months, then slows. New hair starts growing during that time, but it can take 6 to 12 months or more for hair to look full again, because hair grows only about a centimeter a month. Shedding that continues past six months is called chronic telogen effluvium.

Can telogen effluvium cause baldness?

No. The follicles stay alive and keep making new hair, so it doesn’t cause bald patches or permanent loss. Hair may look thinner all over for a few months. If thinning keeps getting worse in one area, such as the part line or crown, ask about pattern hair loss, which can happen at the same time.

Can stress cause telogen effluvium?

Yes. A period of severe emotional stress, such as a death in the family, a divorce or losing a job, can trigger it. The shedding usually starts two to three months later, which is why people often don’t link the two. Ordinary day-to-day stress is less likely to cause noticeable shedding.

Do biotin or other supplements help?

Usually not, unless a blood test shows you are low in something such as iron. Biotin rarely helps people who aren’t deficient, and high doses can throw off some lab results, including thyroid and heart tests. Tell your doctor about any supplements you take before you have blood work.

When to see a doctor

• Shedding that lasts more than six months, or keeps coming back
• Bald patches, a widening part, or a receding hairline
• An itchy, red, scaly or painful scalp
• Hair loss along with tiredness, weight changes, feeling cold or hot, or heavy periods
• Hair loss in a child

Questions to ask your doctor

• Is this telogen effluvium, or could it be another type of hair loss?
• What might have triggered it?
• Should I have my iron and thyroid checked?
• Could any of my medicines be playing a part?
• When should I expect the shedding to stop?

Learn more

• Telogen effluvium (DermNet)
• Hair loss (MedlinePlus, U.S. National Library of Medicine)

This guide is general information and doesn’t replace advice from your own doctor. Last updated October 2026.