Is thyroid disease dangerous? The short answer to that question is “it can be,” yet most complications associated with thyroid disease are preventable with proper management of the condition. That little butterfly-shaped gland in your neck is responsible for many vital bodily functions like metabolism, temperature regulation, and hormone production, so everything gets thrown out of whack when it’s not functioning as it should.
I’ve communicated with countless people who believed the symptoms of thyroid disease they were experiencing, such as fatigue, weight changes, or mood swings, were simply the result of getting older or stress, while their thyroid condition persists. Fortunately, thyroid conditions can be straightforward to manage once you know exactly what you’re dealing with.
The impact of untreated thyroid disease doesn't tend to influence only a single part of the body. It spreads its influence everywhere.
Hyperthyroidism, which is caused by an overactive thyroid gland that overproduces hormones, can trigger an irregular heartbeat for many reasons, including a potassium-sodium imbalance from sweating so much and losing salt while the body struggles to excrete potassium fast enough, while the kidneys are strained. An irregular heartbeat may be associated with conditions that eventually lead to blood clots, stroke, and heart failure. Hyperthyroidism from Graves’ disease is also linked to thyroid eye disease, which can threaten your vision.
Hypothyroidism, caused by an underactive thyroid gland that doesn’t produce enough thyroid hormones, can lead to heart failure when left untreated, and, in extreme cases, myxedema coma—a rare but life-threatening condition.
There’s also the thyroid storm, which is a rare but terrifying condition. It is essentially a combination of issues at the same time that overwhelms the body, such as a viral infection while having hyperthyroidism that can elevate your heart rate, blood pressure, and body temperature to dangerous levels.
A thyroid storm can easily send you to the emergency room and rapid identification of the issue and appropriate treatment are necessary to avoid fatalities. In my experience working with clinicians and presenting on my case, many dietitians told me that they did not know thyroid conditions could result in fatal complications.
During my two emergency room visits for hyperthyroidism, the excessive reliance of the US healthcare system on TSH levels meant that the providers managing my care were unable to evaluate the severity of the danger I was in properly.
They were using a binary metric of TSH present/absent and not looking at my free T4 to assess the level of severity, such as noting that a T4 of 6.1 ng/dl would generally be more symptomatic and extremely dangerous for me versus a T4 of 2.1 ng/dl (normal range usually given as 0.8-1.8 ng/dl).
I remember an older nurse coming into my room and fiddling with my vital signs monitor. They had written in my notes that I was careless with my health and somehow simultaneously a hypochondriac.
In reality, I was self-advocating and troubleshooting calmly with a very elevated heart rate, and this often throws healthcare professionals for a loop, so they try to write off my quantitative measurements as due to anxiety as a woman while also claiming that I can’t be experiencing any issues because my demeanor is calm.
Shockingly, I had to explain to the nurse that hyperthyroidism causes an elevated heart rate, as she didn’t understand how a relaxed woman in her 30s in a seated position would have such a rapid heart rate.
By the time I returned to the emergency room with a severe viral infection obtained at a Christmas party, I had spent approximately three months pulling myself back from extreme hyperthyroidism. My free T4 had fallen from 6.1 ng/dL to approximately 1.8 ng/dL, which was at the upper end of the normal range. My TSH had not yet recovered, but that is common after severe hyperthyroidism. TSH can remain suppressed for months after circulating thyroid hormone levels improve.
That distinction should have mattered. Instead, the clinicians continued to treat my thyroid status as a crude binary. TSH was either detectable or undetectable. They were not asking the question that actually mattered, which was how much active thyroid hormone was still affecting my body.
They never tested my T3, and that omission was not trivial. T3 can remain elevated even after free T4 returns to the normal range. Because they failed to test it, they could not determine whether I had fully recovered biochemically or whether I still had T3-predominant thyrotoxicosis. They also could not responsibly exclude infection-triggered thyrotoxic decompensation, impending thyroid storm, or thyroid storm.
I cannot prove retrospectively that I definitively had thyroid storm. The hospital failed to collect one of the most important tests that might have clarified the diagnosis. What I can say is that they lacked the evidence to rule it out and behaved as though they had ruled it out anyway.
I had a severe inflammatory illness, increasing body temperature, hyponatremia, increased seizure activity, and a resting heart rate of approximately 140 beats per minute while lying down. My body was showing signs of several systems, all destabilizing at once.
I pushed them to order a CBC, metabolic panel, lactate testing, cultures, viral testing, and a kidney function test. The results showed severe systemic inflammation. They did not identify the specific virus or other infectious agent. The reality of the inflammatory illness was not diminished simply because a routine viral panel failed to identify the specific pathogen. Standard hospital panels test for a limited number of infections. My body was clearly responding to something severe.
A serious infection or inflammatory illness is a recognized trigger for thyrotoxic decompensation. I had only recently recovered from a free T4 of 6.1. My T3 status was unknown. My fever was climbing. My sodium was low. My seizures were increasing. My heart was racing at approximately 140 while I was supine and resting.
That should have triggered a formal thyroid storm assessment, repeat thyroid testing that included T3, cardiac monitoring, electrolyte and fluid management, neurological coordination, and continued observation. Instead, their principal response was to offer NSAIDs. That was not a serious treatment plan. It was an attempt to temporarily lower the fever while ignoring the physiological crisis producing it.
At one point, I was lying in the emergency room bed shivering violently and shaking from pain and inflammation. A nurse popped into the room, looked at my monitor, and told me that my heart rate was “a little high.” It was approximately 140 beats per minute while I was lying flat. That is not “a little high” for a woman in her thirties who is supine and not exercising. It is marked resting tachycardia. In my situation, it was occurring alongside escalating fever, severe inflammation, hyponatremia, increased seizure activity, and a recent history of extreme hyperthyroidism.
The nurse fiddled with the monitor, offered no meaningful explanation, and left. She appeared unable to reconcile the number on the screen with the fact that I was speaking calmly. I again had to explain that hyperthyroidism could elevate my heart rate even though I was not running around, panicking, or screaming. My calm demeanor was treated as evidence against the severity of my condition while my actual vital signs were minimized.
The irony was everywhere. The department featured numerous signs instructing patients against touching or adjusting their vital sign monitors, citing the potential inconvenience to nursing staff. Patients were sternly instructed not to interfere with the equipment, but when my monitor displayed a heart rate near 140, the nurse responsible for interpreting it called it “a little high,” adjusted the machine, and walked away.
The signs suggested that the monitors mattered when patients might create extra work. My experience suggested that the readings mattered much less when responding to them would require the staff to reconsider my care.
I was lying there visibly shivering and shaking in pain. The monitor was not displaying an abstract fear I had invented. It was documenting what my body was doing in real time. Instead of asking why my heart was beating so rapidly while I was lying still, the nurse behaved as though the problem might be the machine, my attention to it, or the inconvenience of my concern.
That moment captured the broader failure of the visit. The hospital demanded that patients respect its monitoring systems while its own staff dismissed the information those systems produced.
I naturally have low blood pressure, so I could not simply be given a routine beta blocker without careful monitoring. A beta blocker could have lowered my blood pressure further or suppressed a heart rate that was partially compensating for fever, dehydration, low circulating volume, infection, or impaired cardiac output.
The situation required more sophisticated management. The clinicians needed to evaluate my specific heart rhythm and determine if the rapid heart rate was a compensatory response, if I was volume depleted, or if my cardiac output was compromised. Furthermore, they should have investigated whether the tachycardia was being driven by an infection, persistent thyroid hormone effects, electrolyte imbalances, or a combination of multiple factors. They should have considered a short-acting and closely monitored approach if rate control was necessary and my blood pressure could tolerate it. Instead, they largely did nothing about the heart rate and focused on NSAIDs.
I had already experienced kidney strain during the hyperthyroid period. I was struggling to maintain fluid and electrolyte balance after prolonged sweating and systemic illness. NSAIDs can reduce blood flow through the kidneys, particularly in people who are dehydrated, hypotensive, or physiologically unstable. Even if ibuprofen was not absolutely contraindicated, it was a poor choice to present as the central solution for someone with low baseline blood pressure, hyponatremia, difficulty hydrating, and recent kidney stress.
The hospital also failed to meaningfully address my low sodium. I could not simply drink large amounts of plain water without risking further dilution. While nurses sat at the desk scrolling through TikTok and Instagram and refused to provide me with oral salt, my sister had to leave the emergency room and go to a nearby store to buy iodine-free salt so that I could take oral salt with water.
At a major university hospital, my family had to shop for one of the most basic components of my supportive care because the staff would not adequately respond to a documented electrolyte problem. My sister was not bringing me a snack. She was helping me manage hyponatremia inside a hospital because the hospital staff had effectively left the problem to us.
The hospital had the laboratory results. They had the vital signs. They had my medical history. They had a patient with severe inflammation, recent extreme hyperthyroidism, a supine heart rate near 140, low sodium, worsening seizures, and an escalating fever. But what they did not have was a coherent plan.
After taking the NSAID, I developed severe burning through my throat and esophagus. My throat became so inflamed that lowering my head could trigger laryngospasm and make me feel as though I could not breathe. Mucus further narrowed an already swollen airway.
Rather than reassessing whether the medication had caused or aggravated a serious gastrointestinal and upper airway injury, the hospital discharged me with instructions to alternate ibuprofen and acetaminophen.
Ibuprofen could temporarily reduce pain and fever. It could not correct hyponatremia, restore circulating volume, evaluate or treat an arrhythmia, manage worsening seizures, protect kidney function, address possible myocarditis or cardiac strain, treat thyrotoxic decompensation, or protect an airway that was becoming increasingly restricted. Acetaminophen could reduce fever, but it was not a substitute for monitored care either.
At home, my family members had to rotate shifts and watch me twenty-four hours a day for several days. My fever repeatedly climbed to approximately 104 degrees. As the temperature rose, I began losing the ability to think clearly, organize information, and communicate. My seizure activity worsened as the fever raged. I struggled to communicate remotely with my neurologist while my cognition was deteriorating. Eventually, with my neurologist’s approval, I increased my clonazepam in an effort to control the seizures.
The increased clonazepam helped control the seizures and may have somewhat reduced the sympathetic overactivation affecting my heart rate, but it was not a substitute for cardiac monitoring, electrolyte management, airway assessment, or treatment of the underlying inflammatory process.
My family monitored my breathing, temperature, cognition, seizures, and ability to communicate. I remained upright because lowering my head made the airway restriction worse. I used warm baths and steam to loosen the mucus and help me breathe through the swelling. The baths were part of an improvised attempt to keep my airway open. My throat was already swollen and injured. Mucus further restricted the space available for air. I was struggling to breathe while my fever surged toward 104 degrees Fahrenheit again and again.
This was the home care plan forced upon us after the emergency department sent me away with instructions to take more of the medication that had injured my throat.
I later went to an urgent care center because the throat and esophageal pain remained severe. Instead of listening carefully to the timeline, the clinician argued with me about my need to avoid acidic foods and follow a temporarily alkaline, non-irritating diet while the tissue healed.
The clinician tried to tell me that vomiting had caused the acid burns in my esophagus. When I corrected him that I had not been vomiting, he began arguing with me and still failed to engage with the obvious sequence of events. I had taken NSAIDs while febrile, hyponatremic, physiologically strained, and already concerned about kidney stress. I then developed severe burning through my throat and esophagus, worsening reflux-like symptoms, airway swelling, laryngospasm, and difficulty breathing.
This was the pattern throughout the entire episode. I presented measurable danger, and clinicians responded by debating my interpretation of my own body. A heart rate of approximately 140 while supine became “a little high.” Hyponatremia became something my sister had to manage with salt purchased from a nearby store. Severe inflammatory markers without a named virus became an excuse for diagnostic complacency. Increasing seizures became my responsibility to coordinate with neurology while cognitively impaired. Airway swelling became another symptom I had to survive at home. A severe NSAID reaction became an argument about whether I had vomited, even though I repeatedly said that I had not.
For what they should have done, the clinicians should have asked whether my tachycardia was being driven by fever, hypovolemia, electrolyte disturbance, infection, persistent T3-mediated thyrotoxicosis, cardiac strain, or some combination of these factors. They should have obtained an ECG, monitored my rhythm, assessed perfusion and cardiac function, repeated thyroid testing including T3, corrected fluid and sodium abnormalities, protected kidney function, controlled the fever with medication I could tolerate, assessed my airway, and coordinated with endocrinology and neurology.
Because of my naturally low blood pressure, rate control required caution. That did not justify ignoring a heart rate of 140. It required a more thoughtful plan than either giving a standard beta blocker or doing nothing essentially.
The clinicians also failed to evaluate whether I fulfilled the clinical criteria for an impending thyroid storm or a full thyroid storm. Diagnosing a thyroid storm requires more than checking TSH values, and the condition cannot be dismissed simply because free T4 has dropped to the upper threshold of normal. It is a clinical syndrome involving systemic decompensation, often triggered by infection or another major physiological stressor.
My T3 was never measured. Therefore, the hospital did not know whether I still had T3-predominant thyrotoxicosis. My recent free T4 of 6.1 ng/dl, still-completely suppressed TSH, severe inflammation, escalating fever, resting heart rate near 140, hyponatremia, neurological deterioration, and worsening seizures should have prompted explicit assessment of thyrotoxic decompensation.
I cannot prove that I was in full thyroid storm. The hospital made that harder to determine by failing to order the appropriate thyroid testing. What is clear is that I had a dangerous multisystem illness and that NSAIDs were an inadequate primary response.
They saw a woman speaking calmly and confused composure with safety. In fact, one healthcare worker took my calmness as an invitation to seek emotional comfort from me while I lay there shaking in pain. Knowing about my work in spinal CSF leak care, he told me about the death of his child during childbirth and how the anesthesiology team had blamed his wife. It was a devastating story, but I was the patient. I was febrile, hyponatremic, tachycardic, inflamed, and struggling to remain cognitively present, yet I was placed in the position of absorbing a healthcare worker’s grief while my own medical crisis went inadequately treated.
The healthcare workers treated my self-advocacy as anxiety while simultaneously relying on me to identify the tests they should order, explain the significance of hyperthyroidism, recognize the sodium problem they were ignoring, arrange for my sister to obtain salt from outside the hospital, coordinate seizure treatment with neurology, and manage my own airway after discharge. They dismissed my clinical judgment when it challenged them, then depended on that same judgment when it allowed them to transfer responsibility for my care back onto me.
The fact that I survived does not vindicate their decisions. It exposes how much of the care was transferred onto a dangerously ill patient and her exhausted family. My family provided the continuous observation, oral electrolyte replacement, neurological communication, airway support, temperature monitoring, and bedside care that the hospital should have provided.
Your thyroid gland might be the culprit if you’ve been eating right and exercising and still struggle to lose weight. Low thyroid hormone levels slow down your metabolism, making it more challenging to achieve a caloric deficit. For some people, that means 5 to 10 pounds of weight gain directly related to hypothyroidism. For others, it’s a lot more.
Hypothyroidism isn’t the only type of thyroid disease that can lead to weight gain; about 10% of people with hyperthyroidism actually gain weight instead of losing it, despite their condition speeding up their metabolism. In many cases, the patient’s appetite outpaces their metabolism. In my case, in severe hyperthyroidism, I did not have much appetite because my body was so strained, and I did not lose much weight due to fluid shifts.
I only developed a voracious appetite as my free T4 dropped and my system became less suppressed. In fact, I learned that each wave of increasing appetite correlated with a lowered T4 score. This is why it’s so important to individualize care and compare people’s progress to their own personal baseline.
Patients who receive treatments for hyperthyroidism are also prone to gaining weight afterward as their bodies adjust to returning to normal hormone levels. One study found that 53% of patients with hyperthyroidism gained at least 10% more weight after treatment than they did after getting diagnosed.
Thyroid disease in children is far more common than many parents realize. Nearly 37 out of every 1,000 kids have some form of thyroid disorder.
Kids with hypothyroidism can go into "slow mode." They may constantly feel fatigued, struggle with mental fogginess, and experience lower motivation regarding academics and extracurricular activities. Their growth also slows down, while puberty is delayed.
Hyperthyroidism, like Graves' disease, accounts for about 10% to 15% of childhood thyroid cases and is most likely to affect children between the ages of 10 and 15. These kids might have trouble swallowing, bulging eyes, or may be underweight for their age despite big appetites.
Here’s the real unfortunate part: Thyroid disease in toddlers is often misdiagnosed because the symptoms, such as poor feeding, sluggishness, and constipation, are written off as “just a phase.” Don’t rule out thyroid dysfunction if your child isn’t growing as expected, seems constantly tired, or is falling behind in school. A simple blood test can help catch it or rule it out.
Thyroid disease and the ways it can impact pregnancy is a topic that doesn't get nearly enough attention. Your body's demand for thyroid hormone increases by about 50% during pregnancy, so your thyroid gland is forced to work overtime.
Untreated thyroid disease during pregnancy has been linked to increased risk of miscarriage, high blood pressure disorders, fetal growth restriction, and placental abruption. Graves' disease is the primary cause of hyperthyroidism in pregnant women in the U.S., affecting approximately 1 to 4 out of every 1,000 pregnancies.
I've had more than a few conversations with mothers who carry guilt about their child's neurodivergence, worried that their thyroid issues during pregnancy somehow "caused" it. Let me be clear: you are not to blame. Many iodized salt programs were largely implemented to address maternal iodine needs (as needs are higher during pregnancy and lactation) without considering the U-curve of benefit for iodine for mothers and for the population as a whole. It is public health programs’ fault that they have not done their due diligence in raising awareness of the U-curve of benefit.
Multiple population studies have found that maternal hypothyroidism is associated with a higher likelihood of an autism diagnosis in offspring. One study found that women with thyroid dysfunction before and during pregnancy had a 2.68-fold higher risk of having a child diagnosed with autism. The likelihood amplified with every progressive trimester of thyroid imbalance. The odds more than tripled when hormone production remained deficient throughout all three trimesters.
Crucially, however, chronic hypothyroidism that is properly managed carries no association with autism in offspring. Instead, the risk stems from untreated hormone imbalances. Thus, there is a great need for more awareness of this issue in the US, of the impact of iodine on thyroid conditions, and of better individualized thyroid management.
What does this mean for you? Get your thyroid checked if you're pregnant or planning to be, and be persistent in finding clinicians who understand the importance of thyroid hormones as part of larger hormonal health and fetal development during pregnancy. Having a thyroid condition does not mean you are failing or have failed your child; instead, you are actively protecting them by managing it.
Complications associated with thyroid disease, such as heart issues, weight fluctuations, developmental challenges in children, and pregnancy risks, can all be successfully managed. Therefore, the answer to the question “is thyroid disease dangerous?” is that it’s often only dangerous if left untreated or–at times–mistreated with improper approaches by clinicians. Early awareness and effective treatment are what matter most.
Seek testing for yourself or your child if you notice persistent changes in weight, ongoing fatigue, mood swings, or any of the other symptoms discussed here. If it's for you, listen to your body. If it's for your child, trust your parental instinct.
While a thyroid condition demands expedient investigation, monitoring, and treatment in some form (not necessarily always pharmaceutical), it does not have to dictate how you live your life.
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