Why do I feel sleepy in certain periods of time


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Everyone feels tired, exhausted and exhausted every now and then. There are usually reasons for this: a stressful day at work, intensive sports training, a restless night. But exhaustion can also be a symptom of illness. How do you recognize this? And what can you do about it?

The body and mind have a limited amount of energy. When it is used up, you can feel it immediately: everyday tasks suddenly seem tedious and exhausting. Activities that are normally easy to do become a challenge. Usually exhaustion is not a cause for concern. But if they do lasts longer and there is initially no plausible explanation for this, certain diseases can also be behind it. To the most common causes of tiredness and exhaustion count:

What is exhaustion?
Exhaustion is a state of severe physical and / or mental fatigue, which restricts physical and / or mental performance. After breathing difficulties there is exhaustion the second most common symptomthat general practitioners hear from patients.

Exhaustion: causes

There are two types of fatigue:

  • To physical, so-called "peripheral" fatigue it comes when it's the Musculature lacks energy. This happens, for example, when the muscles have used up their glycogen stores (to put it simply: the sugar stores) during intensive sports training.
  • The "central", mental fatigue goes from the central Nervous system out. It occurs when the balance of messenger substances in the brain shifts.

The two forms of fatigue can be used, however not clearly differentiated from each other. Often they have common causes. A low blood sugar level (hypoglycaemia), for example, can lead to the muscles running out of fuel. On the other hand, the lack of sugar can impair the metabolism of the nerve cells and thus lead to central fatigue.

There are also two forms of fatigue interacting with each other: If the skeletal muscles are overloaded, they can inhibit the central nervous system in order to protect the body from overuse.

First of all, exhaustion is not a sign of illness, but a normal physical condition such as hunger or thirst. If you are, however for no apparent reason and over long periods of time feels exhausted away, this can be a warning sign.

Doctors count exhaustion among the "General symptoms"that occur in many different physical and mental illnesses. Similar to breathing difficulties or headaches, exhaustion is a unspecific, ambiguous symptomfor which there can be innumerable explanations.

To the mental sufferingthat often lead to fatigue include:

Possible physical causes are about:

  • Infectious diseases caused by bacteria (e.g. Lyme borreliosis), fungi and viruses (e.g. the onset of a cold, flu, but also HIV),
  • Sleep disorders (e.g. sleep apnea syndrome),
  • Anemia (anemia, e.g. iron deficiency anemia, vitamin B.12-Defect),
  • Disorders of the hormonal balance (e.g. hypothyroidism),
  • Circulatory diseases (e.g. low blood pressure),
  • a pregnancy,
  • Heart diseases (e.g. heart failure, cardiac arrhythmias, CHD, heart inflammation),
  • Diseases of the central nervous system (e.g. multiple sclerosis),
  • Metabolic diseases (e.g. diabetes mellitus),
  • chronic inflammatory bowel disease (e.g. Crohn's disease, ulcerative colitis),
  • Cancer (e.g. leukemia, lymphoma),
  • Side effects of medication or treatments (e.g. chemotherapy),
  • malnutrition (e.g. due to anorexia, bulimia),
  • Adrenal insufficiency (Addison's disease),
  • Alcoholism, as well
  • Weaknesses and diseases of the immune system.

Another disorder that manifests itself in exhaustion is that chronic fatigue syndrome, also known as chronic fatigue syndrome, fatigue syndrome (French. fatigue = Fatigue) or myalgic encephalomyelitis.

What is Chronic Fatigue Syndrome?
This is a state of permanent fatigue and poor performance that lasts for at least six months. Characteristic of this syndrome is that those affected are self-conscious not feeling better after sleeping and often Pain in muscles, joints, neck and head feel.

Some also complain of tender or swollen lymph nodes on the arms and neck. The causes have not yet been clarified. Because the syndrome often after viral infections occurs as well as in chronic inflammatory autoimmune diseases such as Crohn's disease, scientists suspect that it is with a Immune system disorder could be related.

Exhaustion: diagnosis

Anyone who feels very exhausted, weak and exhausted over a long period of time should relieve their complaints Family doctor let clarify. Since the possible causes of exhaustion are very diverse, the doctor provides the so-called anamnese first some questions:

  • How long have you been feeling exhausted?
  • How exactly is the weakness expressed?
  • Do you feel that your muscles are weaker than usual?
  • Do you feel sleepy during the day and then do you fall asleep?
  • Was there a specific trigger?
  • Do you have any previous illnesses?
  • Do you have certain illnesses in your family?
  • How do you feel about your workload?
  • Do you suffer from insomnia?
  • What is your nutrition like?
  • Have you lost weight?
  • Do you take any medicine?
  • Do you smoke or do you use drugs?
  • Do you have other complaints such as fever, swollen lymph nodes, shortness of breath, pain?

The doctor then performs a physical examination by. For example, it measures blood pressure and takes blood from the patient. The doctor can use the blood values ​​to identify various diseases, for example anemia, high blood sugar values ​​or inflammation. He also examines the patient's skin, since an unusually pronounced and increasing skin tan (pigmentation) can indicate adrenal insufficiency.

Usually (in around 80 percent of cases) the doctor succeeds in making a diagnosis on the basis of the anamnesis and the physical examination. Still are sometimes further investigations necessary to confirm the diagnosis or to clarify certain findings from the examination.

Exhaustion: treatment

Exhaustion goes on one physical or mental illness back, the doctor will do this targeted to treat.

If depression caused exhaustion, so can psychotherapy or antidepressants help.

If the cause is an underactive thyroid, the doctor can prescribe a drug with the active ingredient levothyroxine or L-thyroxine, which replaces the missing thyroid hormone thyroxine. When hormone levels return to normal, exhaustion usually subsides too.

In diabetics, the exhaustion often stems from the fact that it is in their cells Lack of energybecause they are unable to absorb sugar from the blood. If the diabetes is treated (with therapy depending on the type of diabetes), the problem will usually go away.

The chronic fatigue syndrome can so far not heal. While some research suggests that Endurance sports such as swimming, walking, cycling or dancing can alleviate the symptoms of some people affected. Also a special form of physiotherapy, the so-called adapted endurance training ("graded exercise therapy", GET for short) has proven itself in some studies.

However, these forms of treatment are among doctors and patients still controversial. If the syndrome is actually a result of organic disorders, then physical exertion could also involve risks, some fear. In previous studies, however, very few participants reported that the exercise made their health worse.

ICD-10 Diagnostic Key:

You can find the appropriate ICD-10 code for "Exhaustion (fatigue, weakness)" here:


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Last content check:02.08.2017
Last change: 04.05.2020