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Can a Thyroid Problem Cause Anxiety or Depression?

Yes, it can. An underactive thyroid (hypothyroidism) and an overactive thyroid (hyperthyroidism) can each produce anxiety or depression symptoms alongside physical ones. An underactive thyroid slows many body functions and can look like depression: fatigue, low mood, trouble concentrating.

Can a Thyroid Problem Cause Anxiety or Depression?
Mental HealthPhysical Causes of Moodlab-result-explainer
Written By: DocAi Health Editorial Team
Last Updated: 2026-09-30
Medical Disclaimer: This article is for general informational and educational purposes only and is not medical advice. It does not create a doctor-patient relationship and is not a substitute for professional diagnosis or treatment by a qualified healthcare provider. Never disregard or delay seeking professional medical advice because of something you have read here. If you think you may have a medical emergency, call 911 or your local emergency number right away. Health information can change and this guidance is general and US-focused, so consult a licensed clinician in your own country about your specific situation.
Yes, it can. An underactive thyroid (hypothyroidism) and an overactive thyroid (hyperthyroidism) can each produce anxiety or depression symptoms alongside physical ones. An underactive thyroid slows many body functions and can look like depression: fatigue, low mood, trouble concentrating. An overactive thyroid speeds them up and can look like anxiety: a racing heart, restlessness, irritability. Symptoms alone cannot show whether the thyroid is involved, so testing and a clinician's judgment matter. This article explains how thyroid hormone affects mood, how thyroid tests work, how clinicians sort out thyroid-related and other causes, and when to get urgent care.

How Your Thyroid Affects Mood and Brain Chemistry

Your thyroid gland sits at the base of your neck and makes two main hormones, T4 and T3. NIDDK explains that thyroid hormones control the way your body uses energy, so they affect nearly every organ, even the way your heart beats. Thyroid hormone also influences brain regions and chemical signals involved in mood, energy, and the stress response, including serotonin and norepinephrine, which many antidepressant and anti-anxiety medications also affect, although the exact mechanisms are not fully understood. When thyroid hormone runs too low, many body functions slow and mood symptoms can follow a depressive pattern. When it runs too high, the body speeds up, and symptoms can look like anxiety or panic.
This overlap is why clinicians sometimes check thyroid function when someone has new or worsening anxiety or depression, especially if standard treatment is not working as expected or physical features suggest thyroid disease. If you are trying to work out whether what you are feeling is ordinary stress, read Is It Normal Stress or an Anxiety Disorder? Physical symptoms that come with anxiety for reasons unrelated to the thyroid are covered in Physical Symptoms of Anxiety People Don't Realize. This article focuses specifically on what your thyroid has to do with your mood.

Hypothyroidism: When an Underactive Thyroid Looks Like Depression

Hypothyroidism is when your thyroid does not make enough hormone, and many body functions slow down as a result. The mood-related symptoms can look like a depressive episode: persistent low mood, loss of interest in things you used to enjoy, low energy, trouble concentrating or brain fog, and sleeping more than usual while still feeling tired. Depression linked to hypothyroidism can be as serious as depression from any other cause, including thoughts of suicide, and those thoughts need immediate attention whatever is causing them (call or text 988).
Alongside the mood symptoms, hypothyroidism often brings physical symptoms such as weight gain, feeling cold when people around you are comfortable, dry skin, thinning hair, constipation, a hoarse voice, and muscle or joint aches. NIDDK notes that many of these symptoms, especially fatigue and weight gain, are common and do not necessarily mean you have a thyroid problem. It also names Hashimoto's disease, an autoimmune condition in which the immune system attacks the thyroid, as the most common cause of hypothyroidism. Because thyroid function often declines gradually, you may not notice symptoms for months or even years, and mood symptoms can build so slowly that you, or the people around you, may not connect them to your thyroid. Our article on hypothyroidism: causes, symptoms, and treatment covers the condition in more detail. In rare cases, severe untreated hypothyroidism can lead to myxedema coma, an emergency in which the body's functions slow to a life-threatening point. MedlinePlus lists signs such as unresponsiveness, a below-normal body temperature, decreased breathing, and uncharacteristic moods, and a slow heart rate is a late symptom of severe hypothyroidism.

Hyperthyroidism: When an Overactive Thyroid Looks Like Anxiety

Hyperthyroidism is the opposite problem: the thyroid makes too much hormone and speeds the body up. This can produce symptoms that are easy to mistake for a primary anxiety or panic disorder: a racing or pounding heart, shakiness in the hands, feeling on edge or unable to sit still, irritability, trouble sleeping, and sweating or heat intolerance even in a cool room. Hyperthyroidism can also cause weight loss despite a normal or increased appetite and more frequent bowel movements. In some people it causes swelling at the front of the neck, and changes in how the eyes look can occur with Graves' disease, which NIDDK names as the most common cause. Severe hyperthyroidism can also affect thinking and behavior: sudden severe agitation, hallucinations, paranoia, or loss of contact with reality need urgent evaluation, and in a person with severe hyperthyroidism they can be part of a serious thyroid-related complication.
Because panic attacks and hyperthyroidism share so many symptoms, including a racing heart, sweating, trembling, and a sense of dread, clinicians may consider thyroid testing when new anxiety or panic symptoms come with physical features that suggest thyroid disease, or when the overall picture warrants it. Untreated hyperthyroidism can also cause an irregular heartbeat that can lead to blood clots, stroke, or heart failure, so new or persistent palpitations or an irregular heartbeat should be medically evaluated rather than assumed to be anxiety or thyroid disease, and fainting or chest pain needs emergency care (see Atrial Fibrillation: Causes, Symptoms, and Treatment). In rare cases, hyperthyroidism worsens suddenly into thyroid storm. MedlinePlus describes it as a sudden worsening of symptoms that may occur with infection or stress, with fever, decreased alertness, and abdominal pain, and says people need treatment in the hospital.

Who Is More Likely to Have a Thyroid-Related Mood Problem

Certain people are more likely to have a thyroid problem behind new anxiety or depression. NIDDK reports that thyroid disease is more common in women than men and in people older than 60. Having another health condition such as type 1 diabetes, celiac disease, or rheumatoid arthritis is linked to a higher chance of an underactive thyroid. A family history of thyroid disease, radiation treatment to the thyroid, neck, or chest, and past thyroid surgery or radioactive iodine also raise the likelihood. Pregnancy and the months after childbirth are another higher-risk window, both for new thyroid problems and for mood symptoms that can be mistaken for typical postpartum adjustment (see Postpartum Anxiety: Symptoms New Moms Often Mistake for Normal Worry). Falling into one of these groups does not mean you have a thyroid problem, but it is useful context for your clinician when deciding how far to take the workup for anxiety or depression without an obvious cause.

Reading Your Thyroid Labs: TSH, Free T4, and Related Tests

If your clinician already ordered labs, here is what the main numbers can tell you. Thyroid-stimulating hormone, or TSH, is made by the pituitary gland and tells your thyroid how hard to work, so it is usually the first test ordered. According to the American Thyroid Association (ATA), a high TSH usually points to an underactive thyroid, because the pituitary is pushing a sluggish thyroid harder, and a low TSH usually points to an overactive thyroid, because the pituitary is backing off. These patterns mainly apply to primary thyroid disease: a low TSH with a low free T4 can have a different explanation, including a pituitary disorder, so clinicians interpret thyroid tests together rather than relying on TSH alone. NIDDK adds that when the TSH is not normal, at least one other test is needed to help find the cause.
Free T4 measures the thyroid hormone in your blood that is available to your tissues, and it is read alongside TSH. T3 testing is mainly useful when hyperthyroidism is suspected, including when TSH is low but free T4 is normal, and it is generally not the main test for diagnosing hypothyroidism. If autoimmune thyroid disease is suspected, your clinician may also order thyroid antibody tests: TPO antibodies can support a diagnosis of Hashimoto's disease, while TSI or TRAb testing can help evaluate Graves' disease. Antibodies help identify a cause, but TSH and free T4 are what show how the thyroid is actually working.
A range that many labs use for TSH falls roughly between 0.4 and 4.0 milli international units per liter, but treat that only as an illustration. Reference ranges vary by laboratory, assay, age, pregnancy status, and other clinical factors, and NIDDK notes that pregnancy, birth control pills, severe illness, and some medicines such as corticosteroids can change T4 levels without a thyroid problem. Ask your clinician to walk through what your specific numbers mean rather than comparing them with a number you find online. A single abnormal result does not always tell the whole story. Your clinician may repeat testing or order additional thyroid tests depending on the result, your symptoms, medications, and medical history. Our articles on understanding TSH results and a high TSH with normal T4 go deeper.

Thyroid Conditions Doctors Watch for When Mood Symptoms Show Up

A few specific situations come up often during a mood workup. Postpartum thyroiditis can develop in the months after childbirth. The ATA says it occurs in approximately 5 to 10 percent of women in the United States and typically starts with a temporary overactive phase, which can bring anxiety, insomnia, and palpitations and is often overlooked because the symptoms are attributed to the stress of a new baby. An underactive phase can follow, with fatigue and depression. Subclinical hypothyroidism, where TSH is mildly elevated but free T4 is still in the normal range, may be linked to fatigue and low mood in some people, and whether to treat it is a decision for your clinician. Thyroiditis in general, meaning inflammation of the thyroid from a viral illness or another cause, can produce a temporary hyperthyroid phase followed by a temporary hypothyroid phase as the gland recovers, which can make mood symptoms shift over weeks or months.

How Doctors Tell a Thyroid-Driven Mood Symptom from a Primary Mood Disorder

No single sign proves that a mood symptom comes from your thyroid rather than a psychiatric condition, and NIDDK notes that a hyperthyroidism diagnosis cannot be based on symptoms alone because many of its symptoms overlap with those of other diseases. Physical symptoms such as unexplained weight change, temperature intolerance, palpitations, or bowel changes may make thyroid testing particularly relevant, but symptoms alone cannot determine whether the underlying problem is thyroid-related, psychiatric, or both. A clear life stressor, a family history of depression or anxiety, or feelings such as worthlessness or guilt out of proportion to circumstances can raise the possibility of a primary mood or anxiety disorder, but they do not rule out a thyroid problem, and thyroid disease can coexist with major stress. You can read more about that pattern in Major Depressive Disorder: Symptoms, Causes, and Treatment. Many people have both a thyroid condition and a separate anxiety or depressive disorder that needs its own treatment even after thyroid hormone levels are corrected.

Treating the Thyroid, and What Happens to Your Mood

For hypothyroidism, treatment is usually a daily synthetic thyroid hormone called levothyroxine (see Levothyroxine: Uses, Side Effects, and What to Know), with follow-up labs to fine-tune the dose. NIDDK says doctors usually check a blood test about 6 to 8 weeks after starting it and adjust the dose if needed. For hyperthyroidism, treatment options include antithyroid medicine, radioactive iodine, or surgery, depending on the cause and how severe it is, and NIDDK notes that antithyroid medicines may take several weeks or months to bring hormone levels into the normal range. Mood and physical symptoms may improve as thyroid hormone levels return toward the target range, but the timing varies and some symptoms may persist even after thyroid function normalizes.
If anxiety or depression symptoms persist after thyroid levels are stable, talk with your clinician about evaluating and treating the mood symptoms directly rather than waiting longer for thyroid medication to catch up. Normalizing thyroid hormone levels does not automatically resolve an independent anxiety or depressive disorder, and needing that additional care is a common, expected next step.

Living With Both a Thyroid Condition and a Mood Disorder

Thyroid disease and mood disorders are both common, so having both at the same time happens and is not something you caused. A simple symptom log, tracking mood alongside physical symptoms like energy, sleep, and heart rate, can help your clinician see whether your mood is tracking with your thyroid numbers or moving on its own path, especially when paired with a current list of your medications and supplements. High-dose biotin, found in many hair-and-nail supplements, can interfere with some thyroid blood tests and make results look abnormal when thyroid function is actually normal, the ATA notes. Tell your clinician about any biotin before testing, and ask whether and when to pause it before blood is drawn.

When to Seek Medical Care

When to Seek Urgent or Emergency Care

Most thyroid-related mood symptoms build up gradually and are usually not an emergency, but a few thyroid-related and mood-related situations need care right away. This guidance is in addition to, not a replacement for, the general disclaimer above.

Emergency, call 911 or go to the emergency room immediately if:

  • Thoughts of suicide or of harming yourself with a plan, intent, or a feeling that you cannot stay safe (call 911, or call or text 988, the Suicide and Crisis Lifeline)
  • A very fast or irregular heartbeat together with a high fever, severe agitation or confusion, vomiting or belly pain, severe weakness, or other signs of acute illness, which can signal thyroid storm and requires emergency evaluation
  • Extreme sleepiness or unresponsiveness, confusion, a low body temperature, a slow heart rate, or slowed breathing, especially with known or suspected hypothyroidism, which can occur with myxedema coma, a life-threatening complication of severe untreated hypothyroidism
  • Sudden severe agitation, hallucinations, paranoia, or loss of contact with reality, which require urgent evaluation and can occur as part of a serious thyroid-related complication in severe hyperthyroidism
  • Chest pain, fainting, trouble breathing, or a rapid, irregular heartbeat, especially with dizziness or a change in alertness

See a doctor soon (same-day or next available appointment) if:

  • Thoughts of suicide or self-harm without a plan or intent to act (call or text 988 now and contact your clinician the same day)
  • New or persistent palpitations, an irregular heartbeat, tremor, or heat intolerance, especially with unexplained weight loss, which should be checked rather than assumed to be anxiety or thyroid disease
  • Persistent low mood, fatigue, or trouble concentrating along with cold intolerance, constipation, or unexplained weight gain
  • New anxiety or panic attacks that started suddenly, especially with physical symptoms such as a racing heart, sweating, or weight loss
  • Swelling at the front of your neck, or a noticeable change in how your eyes look
  • Mood symptoms that have not improved after your thyroid levels are stable, or that are getting in the way of work, sleep, or relationships
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Frequently Asked Questions

Can hypothyroidism cause anxiety as well as depression?

Yes. While hypothyroidism is more often linked to depression-like symptoms, some people with an underactive thyroid also have anxiety, and a thyroid medication dose that is too high can cause anxiety too. Anxiety may ease as thyroid hormone levels normalize, but if it does not, it may need separate treatment.

Will my anxiety or depression go away once my thyroid levels are back to normal?

Mood and physical symptoms may improve as thyroid hormone levels return toward the target range, but the timing varies and some symptoms may persist even after thyroid function normalizes. Some people still have anxiety or depression after their labs normalize, especially with a separate mood disorder. Normalizing thyroid levels does not automatically resolve an independent anxiety or depressive disorder, which needs its own treatment plan.

What TSH level is considered normal?

Many labs report a TSH reference range of roughly 0.4 to 4.0 milli international units per liter, but that is only an example. Reference ranges vary by laboratory, assay, age, pregnancy status, and other clinical factors. Your clinician interprets your number alongside your free T4, your symptoms, and your medical history rather than a single cutoff, so ask them to walk through what your specific result shows.

Can I have a thyroid problem with anxiety or depression even if my TSH is normal?

The ATA notes that in most healthy people, a normal TSH indicates the thyroid is working properly, but no single test answers every question, and mood symptoms have many possible causes. If your symptoms are significant and thyroid testing looks normal, your clinician may repeat the test or look for other causes. Depending on your symptoms, family history, examination, and initial results, they can decide whether additional thyroid testing is useful.

Is postpartum depression connected to the thyroid?

It can be. Postpartum thyroiditis affects approximately 5 to 10 percent of women in the United States, according to the ATA, and can bring an overactive phase with anxiety, insomnia, and palpitations, an underactive phase with fatigue and depression, or one followed by the other. Clinicians may check thyroid function when postpartum mood symptoms are severe or do not improve as expected. See also Postpartum Depression vs. the "Baby Blues": How to Tell the Difference.

Can thyroid medication itself cause anxiety?

Yes, if the dose is too high for your body. MedlinePlus lists anxiety, palpitations, rapid weight loss, restlessness or tremors, and sweating among the symptoms that suggest a thyroid medicine dose may be too high. Tell your prescriber about new anxiety or a racing heart after a dose change or a new medicine instead of adjusting the dose yourself.

Should everyone with anxiety or depression get their thyroid checked?

Not necessarily. Clinicians may consider thyroid testing when new anxiety or depression comes with physical features suggestive of thyroid disease, is not responding to treatment as expected, or when the clinical picture warrants it. It is not required for every case of mood symptoms, so talk with your clinician about whether it makes sense for your situation.

Can Hashimoto's thyroiditis cause mood changes before hypothyroidism shows up on a blood test?

Thyroid antibodies can be positive before thyroid hormone levels become abnormal, but positive antibodies do not prove that current mood symptoms are being caused by thyroid dysfunction. Fatigue, low mood, and brain fog are common and have many possible causes. If you have a family history of thyroid disease or positive antibodies along with new mood symptoms, mention it to your clinician so they can decide what further evaluation, if any, is useful.

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