Hypothyroidism Hair Loss:
Symptoms & How to Manage It

Written by Kathleen Morrison
Medically Reviewed by Andrea Sleeth WHNP-BC, MSCP

Key takeaways:

• Hypothyroidism (an underactive thyroid) can slow the hair growth cycle, pushing more strands into the resting phase and contributing to diffuse thinning.
• Thyroid-related hair loss often shows up as overall thinning rather than patchy baldness, sometimes alongside drier, coarser texture and outer eyebrow thinning.
• Levothyroxine is the first-line treatment for hypothyroidism and helps normalize thyroid hormone levels, which can restore a healthy hair cycle.
• Minoxidil may be considered to help support cosmetic regrowth while your thyroid hormone levels stabilize.
• Gentle hair care, balanced nutrition, stress management, and consistent sleep may help support overall hair health alongside appropriate treatment.

Your shower drain sees more strands swirling down. Your ponytail has gone from "thick rope" to "suspiciously skinny." And there's a recent hypothyroidism diagnosis in the picture.

Yes, it can all be connected, and hypothyroidism can quietly hijack your hair growth cycle but the good news is that hair often begins to recover once thyroid hormone levels are well managed.

Staying consistent with prescribed levothyroxine is an important part of treatment, and keeping up with refills can help maintain steady hormone levels. Some people may also use treatments like oral minoxidil (if medically appropriate) to support cosmetic regrowth while their thyroid levels stabilize.

Wisp treatment options are available only after consultation with a licensed medical professional, if medically appropriate. You should consult with your healthcare provider before starting a new supplement or treatment regimen. Individual results may vary. Must be 18 or older. For medication details and risks, see site for details.

The link between hypothyroidism and hair loss

The human hair cycle moves through three phases: anagen (growth), catagen (transition), and telogen (resting/shedding).

Thyroid dysfunction can shorten the anagen phase and extend telogen, which means less new hair coming in and more hair shedding going out. Not exactly the math we were hoping for.

Because the hair growth cycle takes months to complete, you usually won't see the effects of a thyroid issue right away.

Translation: today's shedding may be reporting back from a hormonal situation that started a while ago.

How thyroid hormones impact hair growth (and loss)

Your thyroid gland makes hormones that regulate metabolism across your entire body, and that includes the cells inside your hair follicles.

When thyroid hormone levels drop due to hypothyroidism, it naturally impacts your hair growth.

More follicles now shift into the resting phase at once, a pattern often called telogen effluvium.

Weeks or even months later, those resting hairs fall out, which is when you start noticing the extra strands on your pillow.

What hypothyroidism hair loss usually looks like

Hair loss caused by thyroid imbalance has a pretty specific signature, and it's different from male or female pattern baldness.

You'll typically notice:

• Diffuse thinning spread evenly across the scalp (not patchy bald spots)
• A wider part or more scalp hair showing through
• A thinner ponytail or less density overall
• Dry, coarse, or brittle hair that's more prone to breakage
• Thinning at the outer edges of your eyebrows (a pretty classic signal pointing to a thyroid problem)
• Gradual shedding rather than clumps falling out at once

This pattern usually means your hair follicles themselves are intact. They're just on a forced timeout.

Once hormone levels stabilize, those same follicles can typically resume producing hair.

If you're seeing patchy baldness instead of diffuse hair loss, that may point toward alopecia areata (an autoimmune condition that can occur alongside autoimmune thyroid disease) rather than thyroid hormone imbalance alone.

Other thyroid-related symptoms to keep an eye on

Hair changes rarely show up alone with an underactive thyroid. You may also notice:

• Persistent fatigue that doesn't improve with sleep
• Feeling cold when everyone else is comfortable
• Unexplained weight gain
• Brain fog or trouble concentrating
• Dry skin and brittle nails
• Constipation
• Low mood or depression
• Heavier or irregular periods
• Puffy face, especially around the eyes

If several of these are hitting close to home alongside thinning hair, getting your thyroid checked is a smart next step.

Prescription options that help with hypothyroidism hair loss

Once thyroid disease is confirmed, treating the underlying hormone imbalance, often with levothyroxine for hypothyroidism, is an appropriate way to address thyroid-related hair loss.

In some cases, topical minoxidil can help support cosmetic hair regrowth once your thyroid hormone levels stabilize.

Levothyroxine for the upstream cause

Levothyroxine is the first-line option for most people with hypothyroidism. It's a synthetic form of T4 (the main hormone your thyroid produces), and your body converts it to active T3 as needed.

When thyroid hormone levels return to a normal range, your hair follicles can begin to get back into their usual growth pattern.

Most people notice less shedding within a few months, with fuller density typically improving over the next several months.

Patience really is the assignment here, since follicles already in the resting phase need to finish their cycle before new hair pushes through.

Most side effects of levothyroxine occur when your dosage is too high or too low, not because of the medication itself.

Side effects of high dose

• Heart palpitations or increased heart rate
• Tremors (shakiness)
• Increased sweating or heat intolerance
• Unintended weight loss
• Diarrhea or increased bowel movements
• Menstrual irregularities
  

Side effects of low dose

• Persistent fatigue or sluggishness
• Cold intolerance
• Constipation
• Dry skin or hair loss

This is not a complete list of risks and side effects, and others may occur. If symptoms worsen or you notice signs of an allergic reaction, contact a provider right away.

Minoxidil for cosmetic regrowth support

While Levothyroxine works on the underlying thyroid issue, minoxidil may be considered to help support visible regrowth alongside it.

While topical minoxidil is typically the first-line option for hormone-related hair loss in women, your provider may discuss other treatment options based on your needs, medical history, and response to other treatments.

It isn't a replacement for addressing thyroid dysfunction, but it can help support the cosmetic side of things while your hormone levels settle.

Common side effects of Oral Minoxidil may include:

• Hair shedding in the first 2-4 weeks
• Nausea
• Headache
• Dizziness or lightheadedness
• Hypertrichosis (unwanted hair growth on the face and body)
  

Serious side effects include that require in-person medical attention:

• Orthostatic hypotension (decrease in blood pressure when changing positions)
• Fluid retention/swelling in the hands, ankles, or feet
• Rapid or irregular heartbeat
• Pericardial effusion: fluid around the heart (rare but serious)

This is not a complete list of risks and side effects, and others may occur. If symptoms worsen or you notice signs of an allergic reaction, contact a provider right away.

Lifestyle habits that can help support hair health

Medication addresses the hormonal root cause, but daily habits play a supporting role too.

• Prioritize protein at every meal. Hair is largely made of protein, and steady intake may help support follicle activity.
• Mind your iron. Iron deficiency is common with hypothyroidism and during menopause and can worsen hair shedding. Talk to a provider before supplementing.
• Add selenium and zinc-rich foods. Brazil nuts, eggs, fish, and shellfish may help support thyroid and hair health.
• Go easy on high-dose iodine supplements. Excess iodine can worsen autoimmune thyroid conditions. Normal dietary intake from seafood, dairy, and iodized salt is usually plenty.
• Be gentle with your scalp hair. Skip tight hairstyles, minimize heat styling, and use a soft brush to help reduce breakage.
• Manage stress. Chronic stress can trigger telogen effluvium on its own and pile on top of thyroid-related shedding. Try stress-busting techniques such as meditation and journaling.
• Protect your sleep. Consistent 7–9 hours can help support overall hormone balance and the systems your hair depends on.
  

What if your hair loss isn’t hypothyroidism-related?

Quick pause before you connect the dots. Hair loss isn't linked exclusively to hypothyroidism.

There are a few other common causes that deserve a spot on your radar:

• Hyperthyroidism (overactive thyroid): Hyperthyroidism can also cause diffuse hair loss. Like hypothyroidism, hair density often improves once thyroid hormone levels return to a healthy range with treatment. Graves' disease, a common cause of hyperthyroidism, may also contribute to hair shedding until the condition is well controlled.
• Antithyroid medications: Used for hyperthyroidism, antithyroid medications can occasionally contribute to hair loss as a side effect. If you started one and noticed increased shedding afterward, mention it to your prescribing provider.

Note: Other autoimmune diseases (like lupus) can also overlap and affect hair growth.

When to see an in-person provider

Some situations call for specialist support. Consider an in-person provider if:

• Your symptoms persist despite hormone levels in the normal range
• You've had multiple dose adjustments without improvement
• You're pregnant or planning to conceive (thyroid needs shift significantly)
• You have thyroid nodules, a goiter, or other structural concerns
• You're managing multiple hormone conditions at once
  

Bridge the gap between thyroid appointments

Refill gaps happen. Whether you're between providers, sitting on an endocrinology waitlist, or navigating an insurance change, missed thyroid medication can bring symptoms (including hair shedding) back fast.

If you already have a hypothyroidism diagnosis, recent labs, and a current prescription, Wisp's Pill Bridge offers a one-time 90-day supply of your existing Levothyroxine.

And if cosmetic hair support is also on your radar, an Oral Minoxidil consult with a Wisp provider can be a next step worth exploring.

Because your care plan shouldn't fall apart just because life got messy.

Most prescriptions are sent to your pharmacy within 3 hours of completing your patient intake form and secure chat or video call when necessary. Pending retail pharmacy hours.

This blog post is for informational and educational purposes only and should not be taken as professional advice. Always consult with a qualified professional before making any decisions based on the information provided here.