Thyroid Hormone Replacement Therapy
- When patients have their thyroid removed to treat cancer (total thyroidectomy), thyroid hormone replacement therapy will be needed afterwards to ensure thyroid function continues.
- Patients may need more or less thyroid hormone doses. It will depend on their age, comorbidities, weight, and serum hormone levels. Surgery preserving the thyroid gland (partial removal) has decreased the need for hormone therapy — but some patients may need some level of hormone replacement.
- Patient awareness of how the hormone works and their understanding of key symptoms regarding the excess or lack of thyroid hormone can help doctors determine if/when dose adjustments are needed.
- Your care team should be monitoring your blood work to ensure adequate hormone levels.
“One of the first fears of having surgery on the thyroid for cancer is: Am I going to lose my thyroid function and does that mean that my metabolism is going to be thrown off?” Dr. Lisa Orloff, Director of the Endocrine Head & Neck Surgery Program at Stanford Medicine, tells SurvivorNet.
Read MoreWhen Is Thyroid Replacement Therapy Used?
This treatment modality is not restricted to thyroid cancer. Actually, the theory behind it is to increase the thyroid hormone levels whenever they are low, leading to health impairments. There are a variety of indications for thyroid replacement therapy.
However, it is generally indicated after thyroidectomy as follows:
- Total Thyroidectomy: If your entire thyroid gland is removed, you will definitely need lifelong thyroid hormone replacement.
- Partial Thyroidectomy (Lobectomy): If only a portion of the gland is removed, many people still need a certain dose of replacement hormone to maintain normal thyroid hormone levels. Patients undergoing lobectomy may need thyroid hormone therapy thought it is typically only about 20-40% of the time.
- TSH Suppression: Depending on the type and stage of thyroid cancer, your doctor may want to keep your TSH lower than normal to lower the risk of any residual cancer cells growing.
“For somebody who does need their whole thyroid gland removed, one of the main things they need to understand is that they, as we all, need thyroid hormone for normal health, and thankfully, thyroid hormone is available in a pill form or in a supplement form, and the hormone itself is identical chemically to the hormone that our thyroid gland produces,” Dr. Orloff explains.
How the Follow-Up Appointments Work
After surgery, your doctor will start you on a dose of thyroid hormone replacement (often levothyroxine) based on factors such as your weight, age, and surgical findings. If you have any cardiac illness, such as cardiac arrhythmias, the dose will be strictly followed. You’ll have regular blood tests — typically including TSH and sometimes T4 — to see if the dose is correct.
- Dose Adjustments: It can take several weeks to feel the full effect of any dose change because thyroid hormone levels in the body respond gradually. Your doctor may adjust the dose up or down depending on your TSH results and symptoms.
- Long-Term Follow-Up: Once your levels are stable, you might need check-ups every 6 to 12 months.
Hypothyroidism & Hyperthyroidism
Even with regular blood tests, it’s helpful to be aware of how you’re feeling day-to-day. If your dose needs adjusting, you may notice changes in your well-being. Always speak with your medical team if you experience symptoms that concern you.
If you are not getting enough thyroid hormone, a condition known as hypothyroidism, you may experience symptoms like:
- Fatigue and low energy
- Weight gain, despite no changes in diet
- Feeling unusually cold
- Dry skin, hair loss, or brittle nails
- Constipation
- Feeling depressed or having mood changes
- Slow heart rate
If you are getting too much thyroid hormone, a condition known as hyperthyroidism, you may experience symptoms like:
- Feeling jittery or anxious
- Weight loss or difficulty maintaining weight
- Feeling unusually warm or sweating more than usual
- Rapid or irregular heartbeat
- Hand tremors
- Increased bowel movements
- Difficulty sleeping
Important Considerations For Patients
- Take Medication Consistently: The timing of your thyroid hormone dose can affect how well it’s absorbed. Many doctors recommend taking levothyroxine on an empty stomach (usually first thing in the morning, 30-60 minutes before eating or drinking anything other than water).
- Stay Current on Blood Tests: Regular lab work is critical for making sure your hormone levels stay within the right range.
- Keep Track of Symptoms: Jot down any changes in how you feel. Sharing these observations with your doctor will help them tailor your dose more accurately.
- Communicate Any Other Medication Changes: Certain supplements or medications — like calcium, iron, or antacids — can affect the absorption of thyroid hormone. Let your healthcare team know about all other drugs or supplements you’re taking.
- Ask About TSH Targets: Every patient’s TSH target may differ, especially if your doctor is aiming for “TSH suppression.” Make sure you know your target and if it changes over time.
- Lifestyle Considerations: Generally, a healthy diet and regular exercise can support your overall well-being. However, there are no strict dietary restrictions unless advised by your doctor.
“It’s important, I think, for patients and physicians alike to try to optimize the balance of thyroid hormone if a supplement is needed, and to be aware that there’s no one size fits all and there’s not just reliance on blood tests alone, but really relying on a combination of blood tests to show the levels of thyroid hormone and TSH and feedback from a patient as to how they’re feeling so that the supplements can be adjusted if necessary,” Dr. Orloff explains.
Questions To Ask Your Doctor
- Will I need hormone replacement therapy?
- How often will I be monitored after surgery?
- How can I tell if my dose needs adjusting?
- Are there any lifestyle changes I should make while on hormone replace therapy?
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