Hair Shedding for More Than 6 Months: Chronic Telogen Effluvium

A shed after a fever, a birth or a hard stretch usually settles within a few months. Sometimes it keeps going for a year or more, and no trigger turns up. Doctors often call that chronic telogen effluvium.

What it looks like

A 1996 study¹ described 355 patients, nearly all women, with diffuse thinning and shedding that had no clear cause.¹ It reported that the condition:

• Usually affects women aged 30 to 60¹
• Starts abruptly, with or without an obvious trigger¹
• Runs a long, fluctuating course in many patients¹

A companion paper by the same author said most of these women had a full head of hair before it started, and that early shedding can be severe, with hair coming out in handfuls.² It also noted that patients often fear going bald, and called the condition self-limiting in the long run.²

Does it lead to baldness?

The evidence here is small. A dermatologist in Melbourne followed five women for at least seven years:³

	Women	What happened
Kept shedding	4	Shedding rose and fell, but photos showed no visible loss of density3
Developed pattern thinning	1	Confirmed on biopsy within 18 months3

The author said more work is needed to know the long-term course and the risk of pattern thinning.³ Five women can’t settle the question either way.

Is it a separate condition at all?

A 2023 review gathered 18 studies with 1,628 cases, 97.5% of them women.⁴ Its findings:

• None of the studies documented that every other cause had been ruled out.⁴
• There’s no agreed definition of the condition.⁴
• Many cases likely represent early female pattern hair loss or a trigger that was never found.⁴
• Some may be worry about normal shedding, especially in people with long hair.⁴

That doesn’t mean your shedding isn’t happening. It means the label can hide a cause worth chasing.

Treatment

There’s no proven treatment. One clinic reviewed 36 women given low-dose oral minoxidil for this kind of shedding:⁵

• Shedding scores fell at 6 and 12 months.⁵
• 13 of 36 grew extra facial hair; two had brief dizziness and one had ankle swelling.⁵
• There was no placebo group, the authors called for controlled trials, and the senior author holds a patent on detecting and treating excessive shedding.⁵

See oral or topical minoxidil and oral minoxidil monitoring questions.

What to ask for

1. A look for pattern thinning. A widening part or thinner hair on top points that way; see a widening part after 50.
2. A search for triggers. Medicines, diet changes, thyroid and iron are the usual suspects; see thyroid tests and biotin and iron and hair loss after 50.
3. Monthly photos in the same light, so you and your doctor can see whether density is actually changing.

For shorter sheds, see why is my hair shedding so much?

Try: “I’ve been shedding more than usual for about eight months. My photos don’t show my part getting wider, but I’d like to rule out pattern thinning and check my thyroid, iron and medicines.”

Hair, Everywhere covers this in Chapter 5, “The Shed,” in a section called “When the Shed Doesn’t End.” Its Hair Log keeps monthly photos of your part with notes on anything big from the months before, so a long shed has a record your doctor can read. See the book.