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Hypothyroidism (Underactive Thyroid): A Comprehensive Guide

Endocrinology & Psychiatry located in Houston and Katy, TX


Hypothyroidism services offered in Houston and Katy, TX

Understanding our body and the complex systems that help it function normally is paramount to maintaining good health. A vital part of this intricate network is the thyroid gland, which plays an essential role in numerous bodily functions. However, certain situations can disrupt its normal functioning, leading to conditions like Hypothyroidism.

Hypothyroidism, or underactive thyroid, is a health condition that is as subtle as it is significant. Its onset is often slow, with symptoms so unassuming that they can be easily dismissed or attributed to other factors. Yet, if left untreated, hypothyroidism can have profound effects on our health and quality of life, leading to issues like high cholesterol and heart complications.

This comprehensive guide aims to help you understand hypothyroidism better. From its symptoms, risk factors, and causes, to the potential complications if left untreated and how it affects different age groups, the guide provides all the information you need to understand this condition. We also cover advice on when to see a healthcare provider and provide an overview of the treatment process.

Awareness and early detection are crucial in managing hypothyroidism effectively. We hope this guide supports you in your journey to better health.

Hypothyroidism (Underactive Thyroid)


Hypothyroidism, also known as underactive thyroid, is a condition where the thyroid gland doesn't make enough thyroid hormone. Initially, it may not cause noticeable symptoms, but over time, untreated hypothyroidism can lead to other health problems like high cholesterol and heart problems.

Diagnosis is through blood tests, and treatment involves taking thyroid hormone medicine. This treatment is typically simple, safe, and effective once the correct dosage is determined by you and your healthcare provider.


Symptoms of hypothyroidism depend on the severity of the condition and can develop slowly over several years. Early symptoms may be barely noticeable and include fatigue and weight gain. As metabolism continues to slow down, more obvious problems can develop. Symptoms may include:

  • Tiredness
  • Sensitivity to cold
  • Constipation
  • Dry skin
  • Weight gain
  • Puffy face
  • Hoarse voice
  • Coarse hair and skin
  • Muscle weakness
  • Muscle aches, tenderness, and stiffness
  • Irregular or heavier than usual menstrual cycles
  • Thinning hair
  • Slowed heart rate (bradycardia)
  • Depression
  • Memory problems

Hypothyroidism in Infants

Hypothyroidism can occur in anyone, including infants. Most babies born without a thyroid gland or with a malfunctioning gland don't have symptoms right away. If untreated, symptoms start to appear including:

  • Feeding problems
  • Poor growth and weight gain
  • Jaundice
  • Constipation
  • Poor muscle tone
  • Dry skin
  • Hoarse crying
  • Enlarged tongue
  • Umbilical hernia

Untreated hypothyroidism, even mild cases, can lead to severe physical and mental development problems in infants.

Hypothyroidism in Children and Teens

In general, children and teens with hypothyroidism have symptoms similar to adults, but they may also have:

  • Poor growth leading to short stature
  • Delayed development of permanent teeth
  • Delayed puberty
  • Poor mental development

When to See a Doctor

If you're feeling tired for no reason or if you have other symptoms of hypothyroidism, see your healthcare provider. If you're taking thyroid hormone medicine, follow your healthcare provider's advice on how often you need medical appointments for checkups and monitoring your condition and medicine.


Hypothyroidism happens when the thyroid gland doesn't make enough hormones. Conditions or problems that can lead to hypothyroidism include:

  • Autoimmune disease, such as Hashimoto's disease
  • Thyroid surgery
  • Radiation therapy
  • Thyroiditis
  • Certain medications, such as lithium

Less common causes may include birth defects, pituitary disorders, pregnancy, and iodine deficiency.

Risk Factors

You're at an increased risk of hypothyroidism if you:

  • Are a woman
  • Have a family history of thyroid disease
  • Have an autoimmune disease, such as type 1 diabetes or celiac disease
  • Have received treatment for hyperthyroidism
  • Received radiation to your neck or upper chest
  • Have had thyroid surgery


Untreated hypothyroidism can lead to other health problems, including:

  • Goiter
  • Heart problems
  • Peripheral neuropathy
  • Infertility
  • Birth defects
  • Physical and mental development problems in infants
  • Myxedema coma, a rare, life-threatening condition