What Are Some Signs My Thyroid Medication Is Not Working?

The thyroid gland plays a key role in many body functions. It secretes hormones that control the body’s metabolism. The thyroid hormones are responsible for regulating the body’s temperature, the body’s ability to burn calories, nail and skin health, and so much more. If you’ve been diagnosed with a thyroid condition, more than likely, your doctor will prescribe a thyroid hormone medication for you. But even after taking your thyroid medication, you may continue to experience symptoms, making you wonder if your thyroid medication is not working properly.

If your thyroid hormone levels are within the normal range, either too high or too low, you may experience undesirable symptoms. For example, walking the dog may make you feel more tired than usual. You might be sluggish all the time. You could be struggling with weight gain. Or you might feel the heat more than others, have very dry skin, or be nervous and anxious most days.

If any of this sounds familiar, it could be that your thyroid hormone replacement medication or anti-thyroid medication is not working. Please continue reading to learn about some signs and symptoms that may indicate your thyroid medication is not working as it should.

What are the different types of medications used to treat thyroid problems?

There are two main types of thyroid disorders—hypothyroidism (when the thyroid gland does not make enough thyroid hormone naturally) and hyperthyroidism (when the thyroid gland makes hormones in excess).

Medications for hypothyroidism (underactive thyroid gland)

Levothyroxine is the most common medicine used to treat hypothyroidism (when there is too little thyroid hormone production). It is a synthetic form of thyroid hormone T4. Levothyroxine is available in the generic form and under brand names like Synthroid, Tirosint, and Unithroid,

If T4 replacement alone is not enough and your thyroid-stimulating hormone (TSH) levels do not improve, your doctor may also prescribe triiodothyronine (T3) thyroid hormone replacement.

Natural desiccated thyroid

(NDT) is a combination of T3 and T4 thyroid hormones. It is available under brand names such as Nature-Throid, Armour, and NP Thyroid.

With a doctor’s prescription, a specialty or compounding pharmacist can also make a compounded thyroid hormone medication that contains T4 and T3 thyroid hormones in a ratio that meets your specific needs. Compounded thyroid medication typically does not contain the fillers present in other thyroid hormone replacement medications that may cause adverse effects.

Medications for hyperthyroidism (overactive thyroid gland)

Anti-thyroid medications such as methimazole (Tapazole) and propylthiouracil help reduce hyperthyroidism symptoms (overactive thyroid) by preventing the thyroid gland from making too much thyroid hormone.

‍How do I know my thyroid medication is working?

If you have been diagnosed with thyroid disease and are experiencing symptoms, it can be difficult to tell whether your symptoms are because your thyroid medication isn’t working or something else. For example, fatigue and weight gain can be hypothyroidism symptoms but can also occur for many other reasons. Symptoms of hyperthyroidism such as anxiety, changes in menstrual cycles, tremors, or heat sensitivity can also be due to various causes.

Nonetheless, here are some signs your thyroid function is not properly controlled, and your medication may not be working. If you are being treated for hypothyroid symptoms or are on hyperthyroidism treatment, you should seek evaluation by a healthcare professional for signs and symptoms such as:

Rapid heart rate or skipped heartbeats
Nail changes such as onycholysis (nail plate separating), slow nail growth, or brittle nails
Unintentional weight gain or weight loss
Heat or cold intolerance
Gastrointestinal symptoms like unusual constipation or symptoms of celiac disease
Joint pain, muscle aches, and fatigue with normal daily activities

Your doctor may order blood tests to check thyroid hormone levels and other organ functions. Based on your thyroid numbers, they may adjust your thyroid hormone medication and ensure that there is no other underlying cause.

What causes thyroid medication to stop working?

When you are taking medication for thyroid disease (to boost or reduce hormone production in the thyroid gland), there are several things that can affect how well your medication works. For example,

Taking your thyroid medication with or without food can affect its intestinal absorption--it is best to take levothyroxine once daily in the morning, 30 minutes before consuming breakfast or caffeinated beverages. On the other hand, methimazole, prescribed for hyperthyroidism, is typically taken 3 times daily with food.
Taking levothyroxine and other thyroid medicines with certain medications can result in drug interactions and reduce the efficacy of your thyroid medications.
Having digestive and kidney diseases can affect the absorption and excretion of thyroid hormone medications.
Having significant changes in body weight, increasing age, or pregnancy can also affect how well your thyroid medication works.
Missing doses or taking the wrong doses can make your thyroid medication less effective.

What are the symptoms of not enough Synthroid?

Symptoms of not enough Synthroid may include fatigue, cold sensitivity, dry skin, thinning hair, constipation, weight gain, muscle weakness, joint pain, hoarseness, puffiness of the face, increase in blood cholesterol levels, slowed heart rate, heavy or irregular menstrual periods, depression, and memory problems.

What are the signs that thyroid hormone lowering medication isn’t working?

Signs and symptoms that your medication for overactive thyroid isn’t working may include rapid or irregular heartbeat, palpitations, increased appetite, unintentional weight loss, thin skin, brittle or fine hair, difficulty sleeping, anxiety, nervousness, irritability, tremors (shaking or trembling of the hands or fingers), changes in menstruation, changes in bowel movements, fatigue, muscle weakness, goiter (a swelling at the base of your neck), increased heat sensitivity, and excessive sweating.

Wrapping up

The best way to ensure that your thyroid medications are working is to take them exactly as prescribed and to keep all your doctors’ and laboratory appointments. Healthcare providers order thyroid levels not only to diagnose hypothyroidism and hyperthyroidism but also to keep an eye on how well your thyroid medications are working and make dosage adjustments. You may need to take a higher dose, or your doctor may change you to another medication if it appears that your thyroid medication is not working.

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