Understanding the Overlap Between Hypothyroidism and Cushing’s Syndrome

Noticing changes in your body can feel unsettling, especially when you’re not sure what they mean. Whether through research, conversations, or while waiting on test results, you might be spiraling about symptoms, treatment, or diagnosis of hormone-related conditions and find yourself trying to make sense of it all. 

Through a holistic approach, you can gain a better understanding of what’s going on in your body without getting lost in conflicting or confusing information.



Learn how hypothyroidism and Cushing’s syndrome differ, how they relate to one another, and why symptoms can sometimes feel so similar. 

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No, there is no conclusive evidence that hypothyroidism causes Cushing’s syndrome or vice versa. While both conditions concern hormones, these conditions are two distinct endocrine disorders that involve different hormones and underlying mechanisms.

Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormones (T3 and T4), leading to a slower metabolism. It is estimated that nearly 5% of Americans over the age of 12 have hypothyroidism, most of them being women. 

Cushing’s syndrome develops when the body is exposed to excessive levels of cortisol, often due to long-term corticosteroid use, a pituitary tumor, or an adrenal gland disorder.

So why is there so much confusion between the two? Hypothyroidism and Cushing’s syndrome share several similar symptoms, causing one condition to sometimes be mistaken for the other without proper testing.

Hypothyroidism and Cushing’s syndrome are two different endocrine disorders that both affect hormone systems differently but share many similar symptoms. Hypothyroidism slows the metabolism, which may cause:

• Weight gain
• Fatigue
• Cold intolerance
• Dry skin

On the other hand, the excess cortisol present in Cushing’s syndrome leads to symptoms like:

• Weight gain
• Muscle weakness
• High blood pressure
• Easy bruising
• A rounded face 

While both conditions cause fatigue, mood changes, and weight gain, their underlying causes, diagnostic tests, and treatment approaches differ significantly. Because of this symptom overlap, healthcare providers often rely on thyroid function tests and cortisol assessments to accurately distinguish between the two disorders and ensure appropriate treatment.

Understanding the Relationship Between Hypothyroidism and Cushing’s Syndrome

The relationship between hypothyroidism and Cushing’s syndrome highlights the complex interplay within the endocrine system, where changes in one hormone pathway can influence others. 

Thyroid hormones and cortisol both play important roles in regulating metabolism, energy utilization, cardiovascular function, and overall physiological balance. When either hormone becomes deficient or excessive, the body may compensate through adjustments in other hormonal networks, sometimes affecting lab values or clinical presentation.

In clinical experience, patients with Cushing's syndrome may typically have a prevalence of thyroid diseases like hypothyroidism. According to one 2021 study, an evaluation of 59 patients with Cushing’s syndrome found that 30.5% had goiter, 23.7% had primary subclinical hypothyroidism, and 8.4% had hyperthyroidism.



If you’re struggling with symptoms related to hypothyroidism or Cushing’s syndrome, taking a holistic approach to your health may help. Learn how hypothyroidism and Cushing’s syndrome interact and how managing symptoms can be beneficial.

#1: Symptom Overlap Can Lead To Misdiagnosis

One of the most significant ways hypothyroidism and Cushing's syndrome interact is through their overlapping symptoms, which can make accurate diagnosis challenging. 



Both conditions commonly cause:

• Weight gain
• Fatigue
• Depression
• Muscle weakness,
• Menstrual irregularities; and 
• Difficulties with concentration or memory

As a result, patients with one disorder may initially be suspected of having the other, particularly when symptoms develop gradually or present atypically. 

For example, unexplained weight gain and persistent tiredness may be attributed to hypothyroidism when elevated cortisol levels are actually the underlying cause. Similarly, some individuals with hypothyroidism may exhibit symptoms that resemble those seen in Cushing's syndrome. 

Because symptom overlap alone cannot reliably distinguish between the two conditions, healthcare providers typically rely on targeted hormone testing to establish an accurate diagnosis and avoid delays in appropriate treatment. 

#2: Excess Cortisol Can Affect Thyroid Function

Elevated cortisol levels associated with Cushing's syndrome can influence the normal functioning of the thyroid axis, creating changes that may resemble or worsen thyroid-related symptoms, like those present in hypothyroidism. 

Excess cortisol can suppress the release of thyroid-stimulating hormone (TSH) from the pituitary gland and interfere with the conversion of thyroxine (T4) into triiodothyronine (T3), the body's more active thyroid hormone. These effects may reduce the availability of thyroid hormones at the tissue level, contributing to symptoms such as fatigue, reduced energy, and metabolic slowing. 

In some cases, these hormonal alterations can complicate the interpretation of thyroid function tests, making it important for healthcare providers to evaluate both cortisol and thyroid hormone levels when assessing patients with suspected endocrine disorders. 

#3: Hypothyroidism Can Influence Cortisol Metabolism

Hypothyroidism can alter the way the body processes and clears cortisol, the hormone responsible for regulating stress responses and numerous metabolic functions. Because an underactive thyroid slows overall metabolic activity, the breakdown and elimination of cortisol may occur more gradually than normal. This change can influence circulating cortisol levels and occasionally affect the results of endocrine testing. 

While hypothyroidism does not cause the excessive cortisol production seen in Cushing's syndrome, its impact on cortisol metabolism can make hormonal evaluations more complex. For this reason, healthcare providers often consider thyroid status when interpreting cortisol-related test results and investigating symptoms that may suggest an underlying endocrine disorder. 

#4: Both Conditions Can Occur Together

Although hypothyroidism and Cushing's syndrome are separate disorders, it is possible for someone to develop both conditions simultaneously. When this occurs, the combination of hormonal imbalances can create a more complex clinical picture, with symptoms from each condition overlapping or masking one another. 

Patients may experience persistent symptoms despite treatment for one disorder, prompting healthcare providers to investigate additional endocrine causes. Identifying and treating both conditions is essential for restoring hormonal balance and improving overall health outcomes. 

Treatment for hypothyroidism and Cushing’s syndrome depends on the underlying hormonal imbalance and its cause. 

At HealthierU, we understand how difficult it can be to live with health issues that affect your hormones and the endocrine system, and while medical treatments are effective, they don’t always detect underlying causes and manage symptoms. Let our team help supplement your current treatment plan with a holistic approach. Contact us to learn more.

Treating Hypothyroidism and Managing Symptoms

Many people suffering from hypothyroidism are prescribed a synthetic thyroid medication that replaces the hormone that their thyroid gland is unable to produce in sufficient amounts. Treatment is typically individualized based on factors like age, overall health, symptom severity, and blood test results. Patients are monitored regularly to ensure hormone levels remain within the target range. 

While hormone therapy replacement is a common and often effective treatment option, symptoms of the condition might still persist. Patients may also benefit from:

• Eating a balanced diet
• Getting regular physical activity
• Ensuring adequate sleep
• Managing stress

Treating Cushing’s Syndrome and Managing Symptoms

Treatment for Cushing’s syndrome focuses on reducing excess cortisol levels and addressing the underlying cause of the hormone imbalance. When the condition is caused by long-term corticosteroid use, providers may gradually reduce medication dosages or switch to alternative therapies under careful supervision. 

If Cushing’s syndrome results from a tumor in the pituitary or adrenal glands, surgery is often the primary treatment option to remove the growth. In cases where surgery is not fully effective or possible, medications that inhibit cortisol production or block its effects may be used. Radiation therapy is also an option.



Common medications prescribed to control cortisol levels when surgery or radiation is not an option or does not work include:

• Ketoconazole
• Osilodrostat (Istarise)
• Mitotane (Lysodren)
• Levoketoconazole (Recorlev)
• Metyrapone (Metopirone)
• Mifepristone (Korlym, Mifeprex)
• Pasireotide (Signifor)

Can Hypothyroidism Be Mistaken for Cushing’s Syndrome?

Yes. This is especially common during the early stages of hypothyroidism when symptoms are still vague. Both conditions can cause a similar pattern of symptoms that are non-specific and develop gradually, leading to healthcare professionals initially suspecting one condition when the other is actually present.

Can Someone Have Both Hypothyroidism and Cushing’s Syndrome Simultaneously?

Yes. Because these conditions affect different endocrine systems, it is possible for someone to have both hypothyroidism and Cushing’s syndrome at the same time, although it is relatively uncommon. Because each condition arises from separate glands and regulatory pathways, one does not prevent the other; however, having both conditions can make diagnosis more complex.

How Do Healthcare Professionals Differentiate Between Hypothyroidism and Cushing’s Syndrome?

Receiving both a clinical evaluation and targeted hormone testing is the best way to differentiate between hypothyroidism and Cushing’s syndrome since the symptoms alone do overlap. 

Healthcare professionals will:

• Look at the pattern of symptoms
• Perform thyroid function tests
• Run cortisol testing
• Conduct imaging studies if Cushing’s is confirmed

Can Thyroid Medication Cause Cushing’s Syndrome?

No, thyroid medication is not a cause of Cushing’s syndrome. The most common thyroid treatment, levothyroxine, replaces the missing hormone and does not increase cortisol or stimulate cortisol production, which is the cause of Cushing’s syndrome.

While hypothyroidism and Cushing’s syndrome are very different conditions, they can sometimes look and feel surprisingly similar on the surface. Because both can cause changes in weight, energy, mood, and overall well-being, it’s easy to see how one might be mistaken for the other without proper testing. 

At HealthierU, we take a holistic approach to get to the root of your symptoms to best manage your condition and improve how you feel. Dr. Donna Sergi embraces how simple lifestyle changes like diet and nutrition have the power to influence how we live our lives and how our immune system and body respond to ailments. Let us help you harness that power to regain control over your hypothyroidism and Cushing’s syndrome. 



Learn more or schedule your first appointment today.