TSH and Free T4
TSH reflects the signal from your brain to your thyroid. Free T4 measures the available form of the main hormone your thyroid produces. Together, they are the starting point for evaluating most cases of hypothyroidism.
Personalized Thyroid Care
Hypothyroidism Evaluation and Treatment Understand Your Thyroid Health and Available Options
Individualized evaluation for symptoms that may be associated with low thyroid function or Hashimoto’s thyroiditis. Care is guided by your health history, symptoms, laboratory findings, medications, and personal needs.
- Comprehensive evaluation
- Appropriate laboratory testing
- Ongoing clinical monitoring
Understanding Low Thyroid
Hypothyroidism and Hashimoto’s Thyroiditis
Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormone to meet the body’s needs. Because thyroid hormone influences metabolism throughout the body, low levels can affect energy, temperature regulation, digestion, mood, muscles, cholesterol, menstrual cycles, fertility, and cardiovascular function.
Hashimoto’s thyroiditis is an autoimmune condition and a common cause of hypothyroidism. Other causes can include thyroid surgery, radioactive iodine treatment, certain medications, pituitary disease, congenital conditions, and iodine imbalance.
Symptoms alone do not establish a diagnosis.
Fatigue, weight changes, hair loss, low mood, and brain fog
can have several causes. Thyroid function should be
evaluated using appropriate laboratory testing and
clinical context.
Common Symptoms
Signs That May Occur With Hypothyroidism
Symptoms often develop gradually and vary from person to person. Some patients experience few symptoms, while others notice changes across several body systems.
Dry hair or skin
Hair or eyebrow changes
Cold intolerance
Fatigue or low energy
Memory or concentration changes
Muscle aches or weakness
Weight gain or fluid retention
Constipation
Low mood
Menstrual changes
Fertility concerns
Brittle nails
Whole-Body Influence
Thyroid Hormone Helps Regulate Vital Functions
Thyroid hormone supports metabolism and influences multiple systems throughout the body.
Heart Rate
Body Temperature
Muscle Function
Cholesterol Metabolism
Menstrual Cycles
Nervous System
Body Weight
Breathing and Energy Use
Clinical Evaluation
Understanding Your Thyroid Numbers
Testing is selected according to symptoms, health history, medications, pregnancy status, and previous thyroid treatment.
T3: The Active Hormone
Your body converts T4 into T3, which helps cells use energy. We review T3 when clinically useful, alongside symptoms, TSH, free T4, and medication timing. T3 alone does not reliably diagnose an underactive thyroid.
Thyroid Antibodies
TPO and, when appropriate, thyroglobulin (Tg) antibodies help identify Hashimoto’s. Positive antibodies alone do not mean medication is needed; thyroid function helps guide treatment.
Reverse T3
Reverse T3 is an inactive product of T4 breakdown. We review prior results in context, but this test is not routinely recommended for diagnosing hypothyroidism or choosing a medication dose.
Your numbers, in context: We consider how you feel, your health history, and your laboratory results together. Targets are individualized; aiming for upper-range T3 or bottom-range TSH is not appropriate for everyone. Persistent symptoms may also call for a review of sleep, iron levels, medication effects, or other causes.
Treatment Options
Thyroid Hormone Replacement, Selected Thoughtfully
Treatment aims to restore appropriate hormone levels, address thyroid-related symptoms, and avoid over- or undertreatment.
Levothyroxine (T4)
Levothyroxine is molecularly identical to human T4 and remains the standard treatment for most patients.
- Available in multiple formulations
- Dose commonly adjusted using TSH
- Consistent administration supports absorption
Combination T4/T3
For selected nonpregnant adults with persistent symptoms despite adequate T4 treatment, a monitored trial adding liothyronine (T3) may be considered after checking other causes. Studies have not consistently shown combination treatment to be better than T4 alone.
- Alternative causes should be considered first
- T3 levels rise and fall more quickly after each dose
- Symptoms and laboratory values require follow-up
Desiccated Thyroid Extract
Desiccated thyroid extract is animal-derived and contains both T4 and T3. Its hormone ratio differs from normal human thyroid physiology.
- Requires careful patient selection
- Requires dose and symptom monitoring
- Generally avoided during pregnancy
About the term “bioidentical”:
Levothyroxine and liothyronine have the same molecular
structures as human T4 and T3. “Natural” or animal-derived
does not automatically mean safer or more effective.
Autoimmune Thyroid Disease
Understanding Hashimoto’s Thyroiditis
Hashimoto’s is evaluated using thyroid function, clinical findings, and thyroid antibodies when appropriate. Positive antibodies with normal thyroid function do not automatically require medication.
When Hashimoto’s causes clinical hypothyroidism, treatment replaces the hormone the thyroid can no longer produce adequately. Medication does not directly eliminate antibodies.
Personalized Nutritional Support
We may recommend individual nutrients or a combination supplement when your diet, health history, or testing suggests a need. Options can include selenium, zinc, vitamin D, vitamin B12, or iron when a deficiency is identified. The goal is to address a nutritional gap as part of your care.
Selenium supports enzymes that convert T4 to active T3. Some studies show lower thyroid antibody levels with supplementation, but benefits for symptoms or preventing hypothyroidism remain uncertain. More is not always better, and no single supplement is right for everyone.
We review ingredients and total doses across all products to avoid overlap. Added iodine can worsen some autoimmune thyroid conditions, and excess selenium can be harmful. Supplements do not replace prescribed thyroid hormone; iron and calcium also need to be separated from levothyroxine as directed.
Ongoing Care
Getting the Dose and Routine Right
We follow how you feel alongside your laboratory results, medication routine, and side effects. If you take T3, blood-test timing matters because levels change after each dose. Targets and follow-up are personalized rather than based on one “optimal” number.
- Take medication consistently as prescribed.
- Separate levothyroxine from iron, calcium, and certain antacids when directed.
- Tell your provider about biotin because it can interfere with some thyroid laboratory tests.
- Repeat testing after dose or formulation changes and periodically once stable.
- Report new palpitations, tremor, heat intolerance, or unexplained weight loss.
Important Situations
Care Changes With Life Stage and Health History
Pregnancy and Fertility
Thyroid needs often increase during pregnancy. Patients who are pregnant or planning pregnancy should contact their provider promptly.
Heart and Bone Health
Excess thyroid hormone can contribute to abnormal heart rhythms and bone loss, making appropriate dosing and monitoring important.
Persistent Symptoms
When thyroid testing is appropriate but symptoms remain, the next step is a broader clinical review rather than automatically increasing medication.
Personalized Thyroid Care
Discuss Your Thyroid Health
Schedule a consultation to review your symptoms, thyroid history, laboratory findings, current medications, and care options that may be appropriate for you.
Book Your ConsultationThis content is for general education and does not replace medical advice, diagnosis, or treatment. Medication selection and dosing require individual evaluation. Do not start, stop, or change thyroid medication without guidance from a qualified healthcare professional.
