8 Signs Your Thyroid Medication Is Working
Key takeaways:
Normal thyroid hormone levels are necessary for regular growth, development, and metabolism. Hypothyroidism or low thyroid hormone levels can affect how well your body functions in many ways.
If you have hypothyroidism, you may have symptoms like low mood and energy, weight gain, constipation, and hair loss.
With hypothyroidism, you’ll have to take thyroid replacement medication to remain healthy. You can tell if your thyroid medication is working if your thyroid hormone levels return to normal and your symptoms improve.
Table of contents
Thyroid hormone is important for regulating metabolism, growth, mood, and development. When your thyroid hormone levels are low (hypothyroidism), you’ll have to take thyroid hormone replacement to keep them in the normal range. Medications for low thyroid levels are some of the most commonly prescribed medications worldwide.
Hypothyroidism can happen for many different reasons. Some of the main causes of hypothyroidism include inflammation, autoimmune disease, surgery, and radiation.
Regardless of the reason for hypothyroidism, medication will most likely be needed. Let’s take a look at medications used for hypothyroidism and how to know if they’re working.
Medications for hypothyroidism
The goal of medications for hypothyroidism is to get thyroid hormone levels in the normal range. Thyroid hormone is a protein that has iodine bound to it, and it can be replaced in two ways:
T3 is the active form of thyroid hormone — it has three iodine molecules.
T4 has four iodine molecules and gets converted to active T3 by cells throughout the body.
There are three types of medication used to treat hypothyroidism:
Levothyroxine (Synthroid, Levoxyl, Tirosint): Levothyroxine contains synthetic T4.
Liothyronine (Cytomel): Liothyronine contains synthetic T3.
Desiccated thyroid (Armour Thyroid): Desiccated thyroid contains both T3 and T4 from animal sources.
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How to know if your thyroid medication is working
If you have hypothyroidism, a healthcare professional will prescribe a medication to help relieve your symptoms and get your hormone levels into the normal range. After you start taking thyroid hormone medication, it may take a few weeks for your levels to improve.
In the meantime, here are eight signs to help you know that your thyroid medication is working.
1. Normal hormone levels
One of the goals of thyroid hormone therapy is to get your hormone levels into the normal range (being in this range is called “euthyroid”). To determine your levels, a healthcare professional may do a thyroid panel, which is a blood test. This includes a test to check your level of thyroid stimulating hormone (TSH) and other thyroid indicators like T3 and T4.
After your initial full thyroid panel, a healthcare professional may just monitor your TSH level to see if any medication changes are necessary. Once a normal TSH level is reached, you’ll continue to take the same dose of thyroid medication unless you start to have symptoms.
If everything is stable, you may only have your TSH checked once or twice a year.
2. Weight management
Thyroid hormone is critical for normal metabolism. And weight gain is one of the first symptoms people notice when their thyroid is getting sluggish. People who have an underactive thyroid may gain 5 lbs to 10 lbs before being diagnosed with hypothyroidism.
There are many options for thyroid hormone replacement. Learn more about the differences between levothyroxine and Armour Thyroid here.
Navigating hypothyroidism can be challenging. Three people share their journey with levothyroxine and tips they’ve learned along the way.
Pharmacist’s tips for thyroid replacement: Find out how and when to take your thyroid medication for the best results.
After you’ve started treatment, a healthcare professional will check to see if you’re losing the weight you may have gained before you started thyroid medication. You can also start to monitor your weight at home.
Keep in mind that the extra pounds may not melt off as easily as they were gained. It may take some time as your energy levels and metabolism get back to normal. Even with normal thyroid hormone levels, you may need to change your diet — or exercise a bit more — to shed those extra pounds.
3. Improved energy levels
Thyroid hormone helps control the production of energy in the body. When thyroid levels are low, your cells can’t maintain energy levels to get you through the day. That’s why people with hypothyroidism feel tired or fatigued.
Until your thyroid medication is at the correct dose, you might be tempted to boost your energy levels with a sugary snack or caffeinated drink in the afternoon. But your body won’t be able to get the energy boost you’d expect. And increased snacking coupled with slower metabolism will cause more weight gain.
If your thyroid medication is working, you should notice improved energy levels and less fatigue. Most people notice improvement in fatigue within a few weeks of being on the right dose of thyroid medication.
4. Improved cold tolerance
Cold tolerance — like weight and energy levels — is also dependent on healthy metabolism. Your body has to make energy to stay warm. If you have hypothyroidism, your body’s thermostat isn’t able to generate heat when the room temperature drops.
One study compared how much heat people were able to make when they have an underactive thyroid as compared with after they started thyroid medication. Researchers found that people produced more heat when their thyroid levels were normal.
5. Improved mood
Although experts don’t know exactly why, hypothyroidism is strongly linked to low mood and depression. Thyroid replacement hormone frequently improves mood in those with low thyroid hormone levels. And some people with depression and normal thyroid levels see better results when thyroid hormone is used with antidepressants.
6. More regular menstrual cycles (if you menstruate)
The thyroid gland and its hormones are critical for normal menstrual cycles, sexual development, and fertility. If thyroid hormones are too high or too low, it can disrupt menstrual cycles and even cause them to stop altogether (amenorrhea). Once normal thyroid hormone levels are reached, menstrual cycles usually normalize.
7. Less dry skin and reduced hair loss
The condition of your skin and hair are often clues to what’s happening inside your body. What’s happening with the thyroid is no exception. Many people report dry skin and hair loss as one of the first symptoms when their thyroid hormone is low.
With low thyroid hormone levels, hair and skin cells divide more slowly. This can cause hair to fall out and wounds to take longer to heal. Skin cells also make less moisturizing secretions. Fortunately, dry skin and hair loss improve with normal thyroid levels.
8. Improvement in bowel movements
Constipation, stool that’s hard to pass, or needing to strain to have a bowel movement sometimes happens with hypothyroidism. Experts think that low thyroid hormone may slow all body processes, even how fast the bowels move.
They’re not exactly sure how it happens. But the good news is that bowel movements usually improve when you reach normal thyroid hormone levels.
Signs your thyroid medication is too low
The signs that your thyroid medication dose is too low are the same as when you have hypothyroidism. Basically, every system in your body slows down. And if you miss several doses of thyroid medication, you can have the same symptoms.
Some of the signs that your thyroid medication is too low are:
Fatigue
Hair loss, dry skin
Constipation
Cold intolerance
Depression
Irregular menstrual cycles
Weight gain
A healthcare professional will check your thyroid levels after starting you on medication. They’ll adjust your dose based on your symptoms and thyroid tests.
Signs your thyroid medication is too high
The signs that your thyroid medication dose is too high are the same as if you had hyperthyroidism (an overactive thyroid). Some of the signs of high thyroid medication dose include:
Anxiety or nervousness
Racing heart
Diarrhea
Excessive sweating
Weight loss
Heat intolerance
Let a healthcare professional know right away if you have any of these symptoms while taking thyroid medication. They’ll check your thyroid levels and adjust your medication dosage.
Why is your thyroid medication not working like it should?
Getting your thyroid medication dose right is just one step in making sure it works like it should. Here are some of the common reasons you might not be seeing the results you expect:
You switched between Synthroid and generic levothyroxine. If a healthcare professional prescribed brand-name Synthroid, it’s best not to switch to a generic. If you started with generic levothyroxine, you’ll want to stick with the same generic and the same manufacturer.
Your weight has changed quite a bit. As with most medications, if you’ve gained or lost weight, you may need to adjust the dose of your thyroid medication.
You took your thyroid medication with food. You must take Synthroid and levothyroxine on an empty stomach.
You took your thyroid medication with vitamin supplements. Iron and calcium supplements can interfere with how your body absorbs thyroid medications. And biotin can interfere with a thyroid blood test. Stop taking biotin at least 2 days before doing a TSH blood test.
You took your thyroid medication with your stomach medications. Omeprazole (Prilosec), esomeprazole (Nexium), and pantoprazole (Protonix) can interfere with how well thyroid medication works. If you’re taking treatment for stomach acid, your healthcare professional may need to increase the dosage of your thyroid medication.
You started estrogen hormone replacement therapy or birth control. Any form of estrogen can affect your thyroid medication and how it’s absorbed.
You eat a lot of fiber. Many foods and high-fiber fruits and vegetables can interfere with its absorption. Thyroid hormone is best absorbed in a fasted state, in the morning, or 4 hours after your last meal.
Can you take your thyroid medication with coffee?
In studies, coffee reduced the body’s absorption of thyroid medications. That’s why experts recommend that you wait at least 60 minutes between drinking coffee and taking thyroid medication.
Liquid levothyroxine (like Thyquidity) may be an option if you have trouble waiting an hour before your first cup of coffee in the morning. Early research shows that absorption of liquid levothyroxine wasn’t affected by drinking coffee. More studies are needed to validate the data though.
Can any food or supplement help your thyroid medication work better?
Most foods or supplements that interact with thyroid medication slow its absorption rather than help it to work better. That’s why it’s best to do both of the following:
Take your thyroid medication by itself.
Have a waiting period of at least 60 minutes before you eat or take any supplements.
Foods or supplements to avoid taking at the same time as your thyroid replacement medication include:
Walnuts
High-fiber foods (like broccoli, beans, or pumpkin)
Antacids
When should you take your thyroid medication?
You should take your thyroid medication at the same time each day — preferably in the morning. To avoid any food interaction, it’s best to take it about 1 hour before breakfast. That’s because your levothyroxine is most effective on an empty stomach.
For some, it can be difficult to time this dose in the morning. If nighttime dosing is more convenient for this reason, that’s OK too. The best time to take your thyroid medication is any time you can do it consistently.
How long does it take for thyroid medicine to work?
Once you start your thyroid medication, it may take 4 to 6 weeks to notice improvement in symptoms. Some people start feeling better sooner. But some people may need to have their dose adjusted a few times over several months.
Even though you might not notice the medication’s effects, it’s starting to work in your body after the first dose. Don’t stop taking your thyroid medication because you’re not seeing immediate results. Make sure you keep your follow-up appointment and get the necessary blood tests. This will help your prescriber adjust your dose in a timely manner.
Frequently asked questions
Semaglutide (Ozempic) is one medication that can increase the absorption of your thyroid medication. This medication is commonly used for weight loss and Type 2 diabetes. And it can raise your thyroid medication levels.
As a result, a healthcare professional may need to decrease your Synthroid dose while taking it. Talk with your prescriber about the monitoring of your thyroid hormone levels if you’re also taking semaglutide.
Fruits are an essential part of a balanced diet. But citrus fruits — like grapefruit — may interfere with your thyroid replacement medication. Some research shows that grapefruit juice may make your levothyroxine less effective. However, the effect seems to be very small. To be on the safe side, let your prescriber know if you consume a lot of grapefruit.
Drinking water is necessary for overall health. But it won’t reverse thyroid disease on its own. Still, drinking water and staying hydrated is good for helping some of the effects of hypothyroidism — like dry skin and constipation. It’s also generally recommended to take your thyroid medication with water rather than another beverage.
The bottom line
Hypothyroidism (low levels of thyroid hormone) is a common and potentially serious medical condition. Thyroid medication is needed to replace the low levels of natural hormone in the body. It may take a few weeks for your hormone levels to improve after starting the medication. A healthcare professional will monitor your symptoms and thyroid levels to know when you’re on the right dose of thyroid medication.
Why trust our experts?
References
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Endocrine Society. (2022). Drinking coffee does not hinder the absorption of liquid thyroid medication.
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