Hyperthyroidism, also known as overactive thyroid, is a condition in which the thyroid gland produces excess thyroid hormones. This overproduction of hormones can significantly impact how a person thinks, feels and functions on a daily basis. Some of the most common signs and symptoms of hyperthyroidism include nervousness, anxiety, irritability, fatigue, muscle weakness, rapid heartbeat, weight loss despite increased appetite, tremors in the hands, excessive sweating, changes in menstrual cycles, enlarged thyroid gland and more. In this article, we will take a closer look at the various ways hyperthyroidism can influence a person’s behavior and mood.
Nervousness and Anxiety
One of the hallmark signs of hyperthyroidism is increased feelings of nervousness and anxiety. The excess thyroid hormones circulating in the bloodstream essentially put the body into overdrive. This ramps up metabolism, heart rate, blood pressure and stimulates brain activity. As a result, people with hyperthyroidism often describe feeling ” keyed up”, on edge, or unable to relax. The anxiety is often worse in the evening or during periods of stress. Panic attacks can also occur in severe cases. The thyroid hormones act on the sympathetic nervous system, which controls our “fight or flight” stress response. This system is chronically activated in an overactive thyroid state. Medications like beta blockers that counteract adrenaline’s effects on the body are often helpful for alleviating symptoms. Cognitive behavioral therapy can also help patients better manage anxiety levels.
Irritability and Mood Swings
The excess thyroid hormones coursing through the body in hyperthyroidism also make people more emotionally volatile and prone to mood swings. Small frustrations and disappointments can easily escalate into full blown anger outbursts. Individuals may snap or overreact over minor issues they would otherwise shrug off if their thyroid was normal. The irritability, agitation and lack of patience stems from feeling overstimulated and on edge from the hormonal excess. Hyperthyroid patients often have difficulty winding down and relaxing. The moodiness, crankiness and quick temper they display is not intentional, but rather a symptom of their medical condition. With treatment that restores normal thyroid function, the mood swings and irritability generally resolve.
Hyperactivity and Restlessness
People with overactive thyroids tend to display signs of hyperactivity and restlessness as well. They may talk fast, be fidgety or have trouble sitting still and relaxing. Again, the excess thyroid hormones increase activity in the sympathetic nervous system and put the body in a constant state of heightened arousal. Hyperthyroid patients often complain of an unusual sense of nervous energy, jitteriness or feeling “revved up”. They may have racing thoughts, struggle to focus or concentrate, and be easily distracted. The overstimulation makes it difficult to wind down at the end of the day. Patients may toss and turn, have difficulty falling or staying asleep at night. Establishing calming bedtime rituals, engaging in relaxing activities during the day and treatments to control thyroid levels can help manage this restlessness.
Fatigue
Despite the tendency towards hyperactivity in hyperthyroidism, fatigue and exhaustion are also very common. Thyroid hormones regulate metabolism and the use of energy at the cellular level. Even though the excess hormones speed up many bodily processes, they prevent the efficient use of energy by cells. This results in a lack of stamina, frequent tiredness and feeling drained despite an overactive thyroid. Patients may notice their endurance for physical and mental activity is lowered. They may tire more easily when exercising or feel wiped out after minor tasks. Treatment to stabilize thyroid hormone levels helps optimize the body’s energy use and alleviate fatigue.
Heat Intolerance and Increased Sweating
Hyperthyroidism accelerates metabolism, which in turn stimulates heat production in the body. Sufferers often have an aversion to heat and find they sweat excessively and unpredictably. Unexplained sweating is a classic sign of an overactive thyroid. Patients may perspire profusely even in cool conditions. They may kick off the covers at night and prefer to have a fan directly on them. The sweating can occur all over the body or be isolated to certain areas. It can also cause body odor. The sweat glands and thermoregulatory center in the brain become very sensitive to small fluctuations in temperature in those with overactive thyroids. Keeping cool with air conditioning, wearing lightweight clothing and avoiding spicy foods can provide some relief.
Trembling or Shaking Hands
Many people with hyperthyroidism will notice fine tremors in their hands that are most visible when reaching for objects. This happens when the excess thyroid hormones cause muscles to quiver involuntarily. The hands may shake when holding a fork or cup, or when trying to write or draw. The trembling or quivering tends to come and go. It generally happens during times of stress or strong emotion when thyroid hormone secretion increases. It also emerges when the person has gone a long time without eating, as low blood sugar further stimulates thyroid release. The trembling usually resolves once the hyperthyroidism is treated and thyroid levels normalize.
Hair Loss
Temporary hair loss or thinning hair is another common symptom of an overactive thyroid. The thyroid hormones regulate the hair growth cycle. When high levels cause the cycle to speed up, more hair than normal enters the shedding phase at once. Most patients with hyperthyroidism will notice more hair coming out when brushing or washing. Overall hair volume may decrease. However, once the thyroid is controlled, the hair loss usually corrects itself. Proper nutrition, vitamins and reducing stress can help minimize thinning during hyperthyroid flares. In some cases, the hormone imbalance can trigger a type of hair loss called telogen effluvium.
Changes in Bowel Habits
An overactive thyroid can disrupt normal gastrointestinal functioning and bowel habits. Patients may struggle with diarrhea, constipation or an erratic combination of both. They may feel an urgent need to have a bowel movement soon after eating. These issues stem from the excess thyroid hormones speeding up transit time and motility in the digestive tract. Increased appetite from the accelerated metabolism also plays a role. Irritable bowel syndrome is more common in those with thyroid disorders. Getting more fiber, staying hydrated and exercising can provide some relief. If bowel symptoms persist, patients should see a gastroenterologist.
Changes in Menstrual Cycles
Women with hyperthyroidism often experience abnormalities with their menstrual cycles. The excess thyroid hormones interfere with the signals between the brain, pituitary gland and ovaries that control menstruation. Common problems include missed or irregular periods, very light or heavy bleeding, or cycles that are closer together. Women may notice their normally regular periods become unpredictable. Increased thyroid hormone levels can also reduce fertility, making hyperthyroidism a potential cause of difficulty getting pregnant. Once euthyroidism is restored, menstrual disturbances usually resolve as well.
Rapid Heartbeat
A rapid, pounding heartbeat is a signature symptom of hyperthyroidism. Thyroid hormones act directly on heart muscle to stimulate a faster heart rate and stronger contraction force. Patients may notice pronounced heart palpitations, a fluttering sensation in the chest, or their heart skipping beats. Excess thyroid hormone also increases blood volume and makes the blood vessels relax, causing higher blood pressure. The resulting increase in workload on the cardiovascular system produces arrhythmias, shortness of breath, dizziness and other concerning cardiac signs in severe cases.
Muscle Weakness and Fatigue
The thyrotoxic state in hyperthyroidism can weaken muscles and impair physical strength. Patients may notice feeling drained and fatigued after modest exercise. Daily tasks like lifting objects, climbing stairs or even prolonged standing may become challenging. There is often muscle soreness, achiness or discomfort at rest. This muscle fatigue stems from an imbalance between the excitatory and inhibitory nerves controlling muscle contraction. It can also arise from vitamin and mineral deficiencies associated with hyperthyroidism. Treatment helps relieve muscle tiredness, but specific physical therapy exercises also help rebuild lost endurance and strength.
Weight Loss
Unexpected weight loss despite a healthy or even increased appetite is extremely common in hyperthyroidism. The excess thyroid hormones rev up metabolism and calorie burning, causing more rapid fat loss. However, increased food intake associated with the accelerated metabolism often cannot offset the hypermetabolic state. Losing muscle mass also contributes to weight loss. Patients may lose anywhere from 5 to 20 pounds without diet or exercise changes. In most cases, the weight loss will stabilize or even reverse once the hyperthyroidism is under control and metabolism is more balanced.
Difficulty Concentrating
Problems with concentration, focus and short-term memory are very common complaints in hyperthyroidism. The excess thyroid hormones overstimulate brain activity, impairing attention span and mental clarity. Patients may be easily distracted, unable to focus for long periods, or struggle to retain information. Everyday cognitive tasks seem to require more effort. Mental sluggishness, forgetfulness and “brain fog” often result. In particular, multitasking rapidly or switching between topics poses challenges. Treating the thyroid disorder improves concentration as hormone levels normalize.
Conclusion
In summary, hyperthyroidism has multifold effects on a person’s physical state, behavior, mood and cognitive function. The excess thyroid hormones generated in this condition essentially throw the body into overdrive. Patients often complain of anxiety, irritability, hyperactivity alternating with fatigue, heat intolerance, rapid heartbeat, muscle weakness and other symptoms that impact their daily lives. However, restoring normal thyroid function through medication, radioactive iodine or surgery can help reverse these symptoms and allow patients to feel like themselves again. With proper thyroid management, most people with hyperthyroidism can lead full, active lives.