The thyroid is the butterfly-shaped gland at the base of your neck. It produces hormones that regulate your body's energy use, along with many other critical functions.
As part of the endocrine system, the thyroid gland makes and stores hormones that help regulate the body's metabolism in the form of blood pressure, blood temperature and heart rate.
When your thyroid hormone production drops, your body processes slow down and change. Hypothyroidism can affect many different systems in your body.
Undiagnosed thyroid disease puts patients at risk for other ailments, such as cardiovascular diseases, osteoporosis, and infertility.
Thyroid hormone levels may fluctuate over time. These fluctuations may occur as your thyroid condition progresses. Still, other factors like age, hormonal changes, and medication variations may also alter your thyroid hormone levels, producing a variety of symptoms.
Common symptoms of hypothyroidism include:
- Weight gain or increased difficulty losing weight
- Coarse, dry hair or hair loss
- Dry, rough pale skin
- Increased sensitivity to cold
- Muscle cramps and frequent muscle aches
- Memory loss or brain fog
- Irregular menstrual cycles
- Decreased libido
Each patient may have any number of these symptoms, varying in severity.
Reasons for fluctuating thyroid hormone levels
Thyroid disease can progress or stabilize as the year's pass due to any number of reasons:
One of the most common contributing factors of fluctuation in your thyroid levels is your age. As we age, especially women, our thyroid function tends to slow down. According to Harvard Health, of women between the ages 35 and 65, "About 13% of women will have an underactive thyroid, and the proportion rises to 20% among those over 65". A person's age at the onset of a thyroid condition often plays a role in their treatment. Many of the symptoms associated with hypothyroidism resemble the typical side-effects of aging, which may delay treatment. Many women attribute their fatigue, weight gain, and brittle hair and nails to menopause instead of a thyroid issue. Therefore, they may not raise the issue with their doctor or seek treatment.
Medication dosage and potency
Your thyroid levels may also vary due to medication type, potency, and dosage. Variances such as a change in health plans, change in primary care physician, or change in thyroid medication formulations may lead to an adjustment in your thyroid medication dosage or potency. Switching to a new brand of thyroid medication may lead to fluctuation in thyroid levels as your body adjusts.
Interactions with other medications
Specific medications may interfere with your thyroid function and absorption of thyroid medication. Some known interactions occur between thyroid medication and corticosteroids, cholesterol-lowering drugs, corticosteroids, amiodarone, and lithium.
Some prescription meds that can influence thyroid hormones:
- Amiodarone used for heart conditions
- Amphetamines (Vyvanse, Ritalin, Adderall, phentermine) used for ADHD and weight loss
- Anti-seizure meds used for seizures
- Aspirin used for blood thinner
- Beta-blockers (propranolol, metoprolol, atenolol) used for blood pressure
- Bile acid sequestrants used for cholesterol-lowering
- Bromocriptine used for pituitary gland
- Cancer therapies like ipilimumab, Nivolumab, Octreotide
- Cimetidine (Tagamet) used for stomach ulcers
- Diuretics (Acetazolamide, Lasix) used for blood pressure
- Estrogens and estrogen disruptors (including Femara, Clomid, and Tamoxifen) used for birth control, hormone replacement, or fertility treatment
- Glucocorticoids (and prednisone) used as anti-inflammatory
- Haldol used for anxiety
- Iodinated contrast used for radiology
- Ketoconazole used as antifungal agent
- Levodopa used for Parkinson's
- Lithium used as a mood stabilizer
- Metformin used for diabetes
- Methimazole used for hyperthyroidism or Graves' disease
- NSAIDs used as pain meds
- Opiates used for pain
- Phosphate binders used for kidney disease
- Propylthiouracil used for Graves' disease
- Ragland (metoclopramide) used for nausea
- Spironolactone used for PCOS or blood pressure
- Sucralfate used for stomach ulcers
We suggest regular monitoring of your thyroid function during the long-term use of any of the therapies listed above.
To cope with the metabolic demands of pregnancy, the mother's thyroid gland undergoes noticeable modifications.
The surge of pregnancy hormones can cause your TSH, T3, and T4 levels to fluctuate. Because the baby requires additional thyroid stimulating hormones, in most cases, your TSH will decrease, and T3 and T4 will increase. However, in some women, the increase can be too drastic, leading to hyperthyroidism. In others, your T3 and T4 may not increase enough; this is common with hypothyroid women.
As thyroid hormone levels change during pregnancy, the hormone replacement dose may change with them. An expecting mom should test their thyroid hormone levels every month in the first half of pregnancy and may be checked less often during the second half of pregnancy.
The seasons - spring, summer, fall, winter - can affect your thyroid. Interestingly, TSH increases during the colder winter months and decreases during the summer months. In the winter, your body may have difficulty keeping up with its hormonal needs, resulting in the TSH rise.
Work with your doctor to manage thyroid level fluctuations. Finding the right treatment and the proper dosage is a step-by-step process that takes time and requires monitoring. Paloma Health helps to make that process easy and personalized.