Hypothyroidism, underactive thyroid
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Hypothyroidism, also known as underactive thyroid, develops when the thyroid glands do not produce enough thyroid hormone, leading to a slower metabolism. This can cause symptoms such as weight gain, fatigue, and a decreased tolerance for cold temperatures.
Often, early stages of hypothyroidism may not present any symptoms. If left untreated, the condition can lead to serious complications, including heart problems and elevated cholesterol levels.
To diagnose hypothyroidism, healthcare providers typically recommend blood tests. The condition is generally manageable with the right treatment. Your healthcare provider will prescribe the appropriate dosage of medication, and regular follow–ups are essential to effectively control hypothyroidism.
Symptoms
Hypothyroidism is a condition that progresses slowly and may begin with subtle symptoms that are easy to overlook. Initially, symptoms like fatigue and weight gain may be dismissed as aging or stress–related changes. However, as the condition worsens, symptoms become more pronounced.
Common symptoms of hypothyroidism
- Tiredness: Feeling unusually fatigued without a clear reason.
- Sensitivity to cold: Feeling colder than others in the same environment.
- Weight gain: Unexplained weight gain.
- Dry, coarse skin and hair: Noticeable changes in skin and hair texture.
- Puffiness: Swelling of the face.
- Voice changes: A hoarse voice.
- Muscle issues: Weakness, aches, stiffness, and tenderness.
- Menstrual irregularities: Heavier or irregular menstrual cycles.
- Mental health: Experiencing depression and memory problems.
- Other signs: Constipation, slowed heart rate (bradycardia), and thinning hair.
Hypothyroidism in infants
Though rare, infants can also suffer from hypothyroidism, often due to an absent or malfunctioning thyroid gland. Early symptoms might be subtle but can include:
- Feeding difficulties
- Poor growth and weight gain
- Jaundice: Yellowing of the skin and eyes.
- Constipation
- Weak muscle tone
- Dry skin
- Hoarse cry
- Umbilical hernia: Swelling near the belly button.
Without treatment, even mild thyroid issues can lead to severe developmental problems in infants.
Hypothyroidism in children and teens
Children and teens might show symptoms similar to adults but with additional issues related to growth and development:
- Stunted growth: Resulting in shorter stature.
- Dental development: Delayed appearance of permanent teeth.
- Delayed puberty
- Cognitive challenges: Poor mental development.
Consult a healthcare provider if you experience persistent tiredness or other hypothyroidism symptoms. Regular follow–ups are crucial for those on thyroid hormone therapy to ensure proper dosing and to monitor overall health.
This layout is adjusted for clarity, emphasizing the progression and specific impacts of hypothyroidism across different ages.
Causes
The insufficient production of hormones by the thyroid gland results in hypothyroidism. Hypothyroidism can result from the following conditions or issues:
- Inflammation of thyroid glands: When the thyroid gland becomes inflamed, this results to thyroiditis. It could be the result of an infection. Additionally, it can be a result of an autoimmune disease or another thyroid–related condition. The thyroid may suddenly release all of the thyroid hormone it has accumulated due to thyroiditis. This results in hyperthyroidism, an increase in thyroid activity. The thyroid then becomes underactive.
- Medicine: Hypothyroidism can be caused by a number of medications. Lithium is one such medication that is used to address a few mental health conditions. Consult with your healthcare provider about any medications you use and how they affect the thyroid gland.
- Autoimmune disease: The autoimmune condition known as Hashimoto’s disease is the most common cause of hypothyroidism. The immune system’s production of antibodies that target healthy organs results in autoimmune disorders. Thyroid gland involvement in that process can occasionally affect the gland’s hormone–producing capacity.
- Thyroid surgery: Thyroid hormone production can be reduced or stopped entirely through surgery that removes all or part of the gland.
- Radiation therapy: Treatment for head and neck tumors with radiation might damage the thyroid gland and cause hypothyroidism.
Hypothyroidism is less frequently caused by:
- Congenital defect: A dysfunctional thyroid gland might be present in some newborns. Certain individuals are born without a thyroid gland. The cause of the thyroid gland’s improper development is usually unclear. However, a hereditary kind of thyroid disease affects certain children. Many newborns with hypothyroidism don’t exhibit any symptoms at first. One of the reasons is that infant thyroid screening is necessary.
- Pituitary disorder: The inability of the pituitary gland to produce adequate thyroid–stimulating hormone (TSH) is a very uncommon cause of hypothyroidism. This is usually caused by a pituitary gland tumor (benign).
- Pregnancy: Hypothyroidism can occur in certain women during or after pregnancy. Untreated hypothyroidism during pregnancy increases the risk of hypertension, early delivery, and miscarriage. Blood pressure rises significantly in the last three months of pregnancy due to preeclampsia. Additionally, hypothyroidism can have a major impact on the growing fetus.
- Insufficient iodine: Iodine is a mineral that the thyroid gland needs to produce thyroid hormones. Seafood, seaweed, plants cultivated in iodine–rich soil, and iodized salt are the primary sources of iodine. Hypothyroidism can result from insufficient iodine. For those who already have hypothyroidism, too much iodine could worsen the condition. It is normal for people to not get enough iodine in their diets in certain parts of the world.
Risk factors
While hypothyroidism may affect anyone, the following factors put you at higher risk:
- Gender: Hypothyroidism is more common at woman.
- Family history: Having a family member that have history of thyroid disease may increase the likelihood of the condition.
- Autoimmune disease: Increased risk factors include having an autoimmune condition like type 1 diabetes or celiac disease.
- History of treatment: Certain individuals who have undergone treatment for hyperthyroidism, radiation to the neck or upper chest, or thyroid surgery, may increase the risk in developing hypothyroidism.
Diagnosis
Hypothyroidism symptoms can vary widely among individuals and often mimic those of other health conditions, making it challenging to diagnose based solely on symptoms. Instead, diagnosis is typically confirmed through a series of blood tests.
Initial testing:
The primary test for diagnosing hypothyroidism is the thyroid–stimulating hormone (TSH) level check. Elevated TSH levels may indicate hypothyroidism, prompting a retest along with a measurement of the thyroid hormone T–4. A diagnosis of hypothyroidism is generally confirmed if TSH levels are high and T–4 levels are low. In some cases, thyroid hormone T–3 is also measured.
Subclinical hypothyroidism:
If a second test indicates high TSH but normal T–4 and T–3 levels, the condition is likely subclinical hypothyroidism, which typically does not produce noticeable symptoms.
Ongoing management:
TSH tests are crucial for ongoing management of hypothyroidism, helping health care providers adjust medication dosages to achieve optimal thyroid function.
Interference with testing:
Certain medications and supplements, such as biotin (found in multivitamins or as a standalone supplement), can affect the accuracy of thyroid blood tests. It is important to inform your health care provider about any supplements or medications you are taking before undergoing thyroid tests.
Treatment
Treatment for hypothyroidism typically involves daily oral intake of the thyroid hormone medicine levothyroxine. This medication helps return hormone levels to a normal range, alleviating the symptoms of the condition.
Starting treatment
- Initial response: You might start feeling better within one to two weeks of beginning the medication.
- Long–term management: Treatment with levothyroxine is usually lifelong. Your healthcare provider might adjust your dosage periodically, based on annual checks of your TSH (thyroid–stimulating hormone) levels.
Dosage adjustment
- Monitoring: Your TSH levels will be checked 6 to 8 weeks after you start the medication and possibly again six months later to find the correct dosage.
- Side effects: Proper dosage is crucial as too much levothyroxine can lead to tiredness, increased appetite, sleep issues, shakiness, and heart palpitations.
Special considerations
- Brand consistency: Stick to the same brand of medication unless otherwise advised by your healthcare provider, as potency may vary between brands.
- Underlying conditions: Patients with coronary artery disease or severe hypothyroidism may start with a lower dose to gradually adapt their heart to increased metabolism.
Proper administration of levothyroxine
- Timing: Take it on an empty stomach, ideally in the morning, and wait 30 to 60 minutes before eating or taking other medicines. If taken at bedtime, ensure it is at least four hours after the last meal or snack.
- Consistency: Do not skip doses or stop taking the medication without guidance, even if you feel better, to prevent the return of symptoms. If a dose is missed, do not double the dose the next day unless advised.
Interactions
- Diet and supplements: Some foods, supplements, and medicines can interfere with levothyroxine absorption. Discuss with your healthcare provider if you consume large amounts of soy, have a high–fiber diet, or take supplements containing iron, aluminum hydroxide, or calcium.
Subclinical hypothyroidism
- Treatment decision: If diagnosed with subclinical hypothyroidism, discuss the benefits of treatment with your healthcare provider. Treatment may not be necessary for mild increases in TSH, but higher levels within the subclinical range might benefit from thyroid hormone therapy to improve symptoms.
