If you feel lethargic, sleepy or sluggish and have a general lack of energy, it may be concerning to you, but most of the time, if it is short-lived, there isn’t a physical condition that is causing it.

However, if it lasts a long time, it could suggest an underlying medical problem and should be checked out by a doctor.

Common lifestyle causes of tiredness can include a build-up of daily stresses, unhealthy lifestyle choices, such as drinking too much alcohol, and stress and worry caused by workplace problems, for example.

Or, your tiredness may be down to your eating habits. If you think your tiredness is due to your diet, then you should choose to eat little and often, in order to keep your energy levels up. Make sure the food you are choosing is healthy too.

If you believe your tiredness is down to something else, like an underlying health condition, then our doctors can help. We’ll cover off more about this further down the page.

The symptoms of being tired will depend on what’s causing it. However, common things to look out for include:

  • Lack of energy/ always feeling tired
  • Feeling exhausted
  • Anxiety
  • Headache
  • Dizziness
  • Muscle weakness
  • Slow reflexes
  • Impaired decision making or judgement

Often, tiredness is nothing to worry about. However, it can be a symptom of a medical condition, including:

Chronic fatigue syndrome

Chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), usually lasts for a minimum of six months and causes severe tiredness that can be disabling. It is usually accompanied by other symptoms such as muscle pain, joint pain, a sore throat and a headache.

Urinary tract infection

A urinary tract infection (UTI) is often noticed through the common symptoms of a burning pain and the need to pass urine. However, you may have a urinary tract infection where the only symptom is tiredness.

Coeliac disease

Coeliac disease affects one in 100 people across the UK, according to Coeliac UK, although many more people may not realise that they have the condition. A type of food intolerance, coeliac disease causes the body to react badly when gluten is consumed. Gluten is found in cakes, cereals and bread.

Coeliac disease is accompanied by other symptoms as well as tiredness, such as anaemia, weight loss and diarrhoea.

Iron deficiency - anaemia

Anaemia is a very common reason for feeling tired, sluggish and run down, and is common in women who are premenopausal, but can impact anyone. Women who have heavy periods or who are pregnant are particularly prone to anaemia, but men can also feel tired due to iron deficiency disorder too.


PMS (premenstrual syndrome) can affect women’s health and emotions during the days before their period, including making you feel low in energy. You should speak to a doctor if the symptoms are affecting your daily life.

Sleep apnoea

Sleep apnoea happens when your throat becomes floppy during sleep, which results in snoring, reduced blood oxygen levels and interrupted breathing. With sleep interrupted throughout the night, it is common for you to feel exhausted during the next day.

Drinking alcohol, smoking or being overweight can make the condition worse.


Dehydration can cause you to feel tired or sluggish. Drinking plenty of water helps the body to flush out toxins and keep energy levels up.


Diabetes, type one or two, can make you feel very tired. Diabetes has other tell-tale symptoms, such as weight loss, thirst and frequent urination.

Thyroid problems

Feeling tired can be a result of an underactive thyroid gland. With this, you have less of the thyroid hormone, called thyroxine, in your body.

Glandular fever

Glandular fever is a viral infection that causes tiredness, a sore throat, fever and swollen glands in your neck. It typically clears up in six weeks, but can leave you feeling tired for several months after this.


Depression can leave you feeling very tired both mentally and physically.

Seasonal Affective Disorder

Seasonal affective disorder (SAD) is a depressive disorder that has a seasonal pattern, typically experienced in the winter. If you feel particularly tired in the winter months, this could be a potential cause.


Generalised anxiety disorder (GAD) is when you feel anxious a lot of the time and it can cause you to feel tired.

Heart disease

The first signs of heart disease can be tiredness or exhaustion caused from completing everyday tasks.

If you are feeling tired all of the time and do not know the reason why, then it is best to speak to a doctor, who can help you uncover the underlying cause.

If you have tiredness along with other symptoms, such as losing weight without trying to, or coughing up blood, you should also see a doctor. If your tiredness is being caused by a medical disorder, a doctor can investigate this further with you, or refer you to a specialist for investigations.

At Push Doctor, you can see a GP online through any device, from work, home or even on the go. They can listen to your symptoms and create a treatment plan for you that will get you back on your feet as soon as is possible. The treatment will usually depend on the underlying cause of your tiredness.

Our doctors are ready to help and you can contact them seven days a week. Book an appointment now.

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