I’m on Thyroid Medication but Still Feel Tired!

Originally published on 4th April 2016
Last updated on 8th April 2024

Are you on thyroid medication but still don’t feel well? A lot of thyroid patients feel this way. They might even question if their thyroid medication is working at all. 

Many people are often left confused and wondering:

• Why am I feeling extremely tired on Levothyroxine?
• My thyroid meds make me tired!
• Does thyroid medicine make you sleepy?

Their doctor puts them on thyroid medication and tells them they are now adequately treated. They may even do a blood test and tell them that their levels are ‘normal’. So then why do they still feel tired?

Can thyroid medicine make you feel tired?

I definitely wondered this as I struggled with my hypothyroidism and Hashimoto’s diagnosis in 2015. I only felt worse as time went on, despite being on thyroid medication. I go in-depth in my bestselling thyroid book “Be Your Own Thyroid Advocate: When You’re Sick and Tired of Being Sick and Tired”, but in this article I’ll give an overview. Be sure to check out the book for even more useful information that will help you to get better.

There are some reasons you can still feel unwell and I’m going to explore the most common ones below.

Related Post: 10 Ways To Solve Ongoing Thyroid Fatigue

1. Your Thyroid Levels Aren’t Optimal

Most doctors will prescribe T4-only thyroid medications such as Levothyroxine and then test your thyroid levels again a month or two later and declare them ‘normal’.

One part of this problem is that most doctors only test TSH levels and this isn’t accurate when getting the full picture of your thyroid health.

In order to know if your thyroid levels are actually optimal, you need a full Thyroid Panel checking, and this should include:

• TSH
• Free T3
• Free T4
• and if possible: TPOAB and TGAB (thyroid antibodies)

Checking TSH alone doesn’t give us the full picture and can miss a low Free T3 or low Free T4 level, indicating that our dosage of thyroid medication isn’t right.

It also isn’t checking for Hashimoto’s, the most common cause of hypothyroidism, which can cause symptoms too.

If your doctor won’t order the full thyroid panel, do know that it is simple to order these tests yourself. UK thyroid patients can order them from here and a US here.

Now that we know what needs to be tested, let’s explore where they ‘should’ sit to help us feel our best.

Most thyroid patients seem to feel best when their levels are also optimised and not just in range.

When your doctor runs a test and you receive the results, your levels will either fall inside or outside of the range. Ranges are usually given in brackets besides the test result.

However, it is not just about falling within the range. We are looking for something more specific.

‘Optimal levels’ are a more specific section within the given range, which is often very wide and much less specific in comparison.

You’ll find that many thyroid advocacies and progressive medical practitioners agree that when testing a thyroid panel (or “Thyroid Function Test”), a TSH less than 2 or 2.5, and a Free T3 in the top quarter of the range, with a Free T4 mid-range or a little higher is considered optimal. Antibodies as low as possible are also seen as optimal as this signals Hashimoto’s being more under control or ‘in remission‘.

Read more about optimal levels here.

2. Your Medication Isn’t Right for You

Some people respond well to Levothyroxine or Synthroid, the T4-only medications, but many equally do not. You may be on this medication and still feel tired, brain fogged, achy and generally unwell. 

After all, a study in 2018 demonstrated that Levothyroxine was associated with a lower quality of life in those with Hypothyroidism. [1]

So you may well do better on a different type if you’re still not feeling well on T4-only medications such as Levothyroxine.

Other thyroid medication options include adding T3 to your T4, or switching completely to Natural Desiccated Thyroid. I’ve covered all of these in detail here and here.

Especially if you have a full thyroid panel tested, and your Free T3 is low yet Free T4 high in range for example, you would benefit from exploring the possibility of a conversion problem and adding that T3 in. This can be done by adding T3 to your T4 (Levo), or switching to NDT, which has it in. These can be discussed with your doctor.

I support people finding what medicine works for them. We are all different.

Thyroid UK reported:

“Levothyroxine treatment provided total relief of symptoms in 7% of the respondents and significant relief in 41% of respondents. However, 6% of respondents received no relief from symptoms and 40% only slight relief. NDT provides the most relief of symptoms providing 29% with a total relief of symptoms and 57% with significant improvement. However, 10% only received slight relief and 2% no relief of symptoms.”

and that is a huge difference. [2]

If your current doctor isn’t open to exploring other medication options, you may wish to explore other types of medical professionals which may be able to help. See types here.

3. There’s Something Else at Play

Other deficiencies or issues are common if you also have thyroid problems. These can include the below, so they’re worth exploring if you still don’t feel well.

Vitamin Deficiencies such as D, B12, Iron, Ferritin etc. can all give you similar symptoms to low thyroid function, so it’s worth checking these if you are tired a lot, have hair loss, bruise easily, are fatigued etc.

Adrenal dysfunction can also cause havoc in thyroid patients too, without us even realising. Symptoms include fatigue, waking up still feeling tired, not being able to cope with stress very well and craving sugary and salty foods. The most accurate way to test if you have adrenal dysfunction is with a 24-hour saliva cortisol test, to check cortisol levels. If your doctor won’t do this, you can very simply order it yourself and complete it at home. If your doctor won’t check your adrenals, you can very simply order testing yourself from here and here. They should ideally read as stated here.

4. You’re Not Addressing Hashimoto’s

Most of us with hypothyroidism have Hashimoto’s to thank as the cause, yet don’t even know it.

I’ve created a whole article on Hashimoto’s here, and ways to treat it include getting your thyroid levels optimal (TSH, Free T3 and Free T4, Thyroid antibodies) and for a lot of patients, cutting out gluten.

More ways to help Hashi’s are listed here.

Addressing the autoimmune condition that may be causing your hypothyroidism and getting it under control can help with fatigue and managing symptoms.

Getting Hashimoto’s in to remission seriously helped in the management of my symptoms.

5. You May be Taking Your Thyroid Medication Wrong

Many patients take their thyroid medication an hour away from any food or drink, excluding water. The reason being to stop anything else from affecting its absorption. You shouldn’t really eat or drink anything for an hour either side of your thyroid meds, as well as take other medication or supplements, and you should avoid taking calcium, magnesium, contraceptive pills and iron close to it in particular. Take your thyroid medication at least four hours away from these.

Oestrogen, calcium, magnesium and iron bind some of the thyroid hormones and makes them unusable, affecting how much you really absorb. If you’re on NDT, many also state that taking it sub-lingually (dissolved under the tongue) has a better effect than just swallowing it.

See a full article on how to correctly take your medication here.

Some patients on T4-only meds like Levothyroxine also state it works better for them when taken at night, instead of the morning.

6. You’ve Not Got The Right Diet 

You’ve got to nourish to flourish!

Eating and drinking in the right way for your body is often key, too. You can explore whether removing caffeine, alcohol or other food that commonly impacts thyroid patients, helps you too. As well as foods that may be problematic, there are also plenty that we should try to get more of to support our thyroid health and reduce thyroid symptoms. More info here.

Find a thyroid cookbook here.

Conclusion

Considering and implementing these ideas can go a long way in seeing improvements. You see, thyroid medication doesn’t cause fatigue, but it may not be addressing it because it’s not the right type or dosage for you. Beyond that, other issues often coexist that we can explore. Living well with thyroid disease often involves looking at our lifestyles holistically and considering all areas.

Do you still feel unwell despite being on thyroid medication? You can share in the comments below.

Related posts:

6 Ways to Create an Energy-Boosting Morning Routine as a Thyroid Patient

When Thyroid Medication Doesn’t Fix Everything

See also:

The book Be Your Own Thyroid Advocate: When You’re Sick and Tired of Being Sick and Tired, which builds on this article in detail. Learn how Rachel reclaimed her life when thyroid medication wasn’t helping.

References:

[1] https://www.healio.com/endocrinology/thyroid/news/online/%7Beb193222-2795-4321-8761-607131d2f743%7D/levothyroxine-therapy-associated-with-lower-quality-of-life-in-hypothyroidism?fbclid=IwAR0Dk8tGRAxB6at_Mc7jgDiPyp0YikRuy6ZmG6yS8CMOz3lPEj67zH_g4vY

[2] http://www.thyroiduk.org.uk/tuk/campaigns/Patient-Expereince-Survey.html