The words tiredness and fatigue are often used to refer to the same physical feelings in general conversation. For anyone who has ever experienced fatigue, it is totally different from tiredness. While a good night’s sleep will usually resolve tiredness, fatigue will not just go away overnight.

Feelings of tiredness and fatigue are a common symptom of some thyroid disorders and we are frequently contacted by patients who are struggling with day-to-day life because of it. One member describes fatigue as: "Feeling constantly drained, sometimes to the point where I cannot physically move." Another member living with Graves’ disease says: "I used to get home from work and fall asleep almost immediately."

There are many reasons for experiencing tiredness and fatigue. In people living with an underactive thyroid(hypothyroidism), the body’s metabolism slows down. This can often lead to many symptoms, including lethargy and fatigue. In people with an overactive thyroid (hyperthyroidism), the body’s metabolism speeds up. This overactivity can lead to fatigue as well as difficulty sleeping.

Where daily hormone replacements tablets, such as levothyroxine, are prescribed for an underactive thyroid, symptoms including fatigue should gradually begin to disappear. Similarly, patients receiving anti-thyroid drugs for an overactive thyroid should begin to see an improvement in their energy levels.


"I am taking my thyroid medication but still feel exhausted all the time."

Frustratingly, for some of us feelings of fatigue can persist even once on medication. Some of the following tips may help your medication to work more effectively:

  • Take your medication consistently every day as failure to do this can affect your blood test results and your health

  • If you forget to take a dose, take it as soon as you remember

  • Antithyroid drugs for hyperthyroidism can be taken either consistently with meals or on an empty stomach

  • To aid the effectiveness of levothyroxine try to swallow your tablets with water on an empty stomach and avoid eating for 30 minutes afterwards

  • It is also best taken at least four hours apart from calcium, iron, cholesterol-lowering drugs (cholestyramine, colestipol), and multivitamin tablets that contain iron, as these can decrease absorption. Grapefruit can also interfere with its absorption.

  • If you wish to take soya, there should be at least a four hour time interval between consuming the soya products and taking levothyroxine, as it interferes with its absorption

  • It is always advisable to tell your doctor if you are taking any other medicines, supplements or special foods as some can interfere with levothyroxine absorption

"Can following a special diet boost my energy levels?"


When feeling low in energy levels, it is tempting to reach for sugary snacks. Whilst these can boost your energy levels temporarily, the surge in energy is often followed by a dip making you feel worse again. By replacing sweet treats with healthier options, including proteins such as lean meat, fish, eggs and fats contained in avocados, nuts and seeds, you can help balance your blood sugar levels.

Avoiding or reducing caffeine can help with your sleep and may make you feel less tired. Reducing alcohol levels may also improve your sleep quality.


If you have hypothyroidism or hyperthyroidism you are advised to avoid preparations and supplements high in iodine as it can make your condition worse. Similarly, avoid products such as kelp, as they may interfere with thyroid function & wellbeing. Kelp is derived from seaweed and is naturally high in iodine. Because of this it is sometimes marketed as a ‘thyroid booster’ and can be purchased in dry preparations and tablets. As with iodine itself, it is of no health benefit to those with thyroid disease, and in the case of hyperthyroidism may aggravate your symptoms, including fatigue.

"I’m shattered but I still can’t sleep at night"


When we are feeling tired all the time, sleep can become an obsession yet it often evades us. Some of the following tips may help you to improve your quality of sleep:

  • Introduce a bedtime routine. By having a bath or reading a book before bed, this can help you unwind

  • Avoid electronic devices – try to turn off electronic devices at least an hour before bedtime and do not keep them next to you in the bedroom thus reducing the temptation to look at screens.

Try to keep regular sleeping hours so the body’s sleeping patterns do not become confused

"What about exercise?"

It may not seem to be common sense to use up precious energy levels by exercising. However, exercise can improve both your energy levels and mood. Exercise does not need to be vigorous and often activities such as yoga and meditation can help you to relax.

"It’s all getting too much for me. What can I do?"

It’s easy to feel overwhelmed when you are lacking in energy. The following tips may be worth a try:

  • Prioritise your tasks – are there some things that can wait or you can ask someone else to do? Perhaps starting with the smaller tasks can make things seem less overwhelming

  • Organise your living space so it works for you – by making practical changes in the home or workplace, you may be able to save your energy. For example, could moving appliances around save you having to get up and down repeatedly?

  • Rest – building rest into your day can help you to manage your fatigue. With a bit of trial and error, you can establish what rest patterns work best for you.

    Where symptoms of fatigue persist, we would recommend you see your GP.