15 common causes of drowsiness

A feeling of being wrapped in cotton wool – one perceives the surroundings to a limited extent, reacts more slowly and feels “half asleep”. Drowsiness is a condition that is usually perceived as unpleasant and can have a variety of causes. We explain what can be behind lightheadedness and what you can do about it.

What is daze?

According to the medical definition, drowsiness is the mildest quantitative consciousness disorder. This means that when you are conscious, your alertness (vigilance) is reduced.

The increases in drowsiness are somnolence (sleepiness), sopor (a deep sleep-like state), and coma. Disturbances of consciousness, which can manifest themselves, for example, in confusion or disorientation, must be distinguished from quantitative disturbances of consciousness.

 

Drowsiness and accompanying symptoms

When you are dizzy, thinking and acting are slowed, perception is delayed, and information processing is limited. Difficulty concentrating often occurs, and attention and memory can also be reduced. Drowsiness is expected to be accompanied by dizziness, pressure in the head or tiredness.

What causes drowsiness?

There can be various harmless causes behind drowsiness, but a feeling of drowsiness can also manifest serious illnesses. We have put together an overview of possible causes of drowsiness for you:

1. Dehydration:  A lack of fluids can make itself felt through drowsiness – usually in combination with tiredness and headaches. So make sure you always drink enough water. A good guideline is roughly two litres per day.
2. Low blood pressure or slow pulse: Drowsiness, especially when combined with dizziness, can indicate a circulatory problem.
3. Lack of sleep: Besides tiredness, too little sleep can cause lightheadedness.
4. Alcohol consumption:  Both in the acute intoxication and the “hangover” the morning after, it can lead to drowsiness in the head.
5. Drugs such as cannabis, ecstasy, or “knockout drops” can cause drowsiness.
6. Infections: An infection like the Epstein-Barr virus, Lyme disease or the flu can lead to pronounced tiredness, exhaustion and drowsiness. These accompanying symptoms can sometimes persist for a few weeks after the illness.
7. Cervical spine syndrome: As part of a cervical spine syndrome, which can be caused by tension or signs of wear and tear on the cervical spine (cervical spine), dizziness and drowsiness can occur.
8. Hypothyroidism: When the thyroid gland is underactive, the entire metabolism is slowed down – symptoms include tiredness, lack of concentration and drowsiness.
9. Blood sugar imbalances: Low or high blood sugar levels can occur, especially with diabetes mellitus, which can lead to drowsiness.
10. Head injuries  (cranial trauma): Severe drowsiness can occur after falls, bumps or hits to the head – for example, as part of a concussion or cerebral haemorrhage.
11. Stroke:  In the case of an acute circulatory disorder of the brain, such as a stroke, neurological symptoms such as paralysis visual and speech disorders usually occur. However, in some cases, non-specific symptoms such as lightheadedness, head pressure and dizziness are the only signs.
12. Meningitis: In addition to impaired consciousness, symptoms of meningitis include drowsiness, headaches, fever, and neck tension (neck stiffness). 
13. Brain tumour:  A mass in the brain, such as a tumour or abscess, can increase intracranial pressure, leading to impaired consciousness. However, these are infrequent causes of drowsiness.
14. Psychological causes:  In the context of mental illnesses such as depression, anxiety disorders or borderline disorders, drowsiness can occur. Stress can also be a possible trigger for drowsiness.

 

1. Cause: Drug drowsiness

Many medications can cause drowsiness as a side effect. These include, in particular, sedatives and sleeping pills, which can lead to a “hangover” the following day if they are taken too late in the evening. Other medications that can cause drowsiness include:

• Antihistamines such as dimetinden (Fenistil®), doxylamine (Hoggar® Night) or dimenhydrinate (Vomex®) are used against allergies,  sleep disorders and nausea. They act on the central nervous system, making you tired and dizzy.
• Antipsychotics act on the psyche and are used, for example, in schizophrenia. In particular, the so-called low-potency antipsychotics such as pipamperone can lead to drowsiness as a side effect.
• Antihypertensives such as beta-blockers and ACE inhibitors, especially in high doses, can cause dizziness by lowering blood pressure.
• Antidepressants such as amitriptyline are not only effective against depression but can also be used to treat chronic pain. Fatigue and drowsiness are common side effects.
• Opiates like tramadol and morphine are strong painkillers that can cause drowsiness.

This is just a selection of the groups of drugs where drowsiness is a widespread side effect. Many other medicines can cause drowsiness in some people.

What to do about drowsiness?

Drowsiness is not a disease but a symptom, the cause of which must be found. Therefore, the question “How do you treat drowsiness?” can not be answered in general.

Nevertheless, you can try a few tricks to get to the bottom of the feeling of drowsiness:

• Drink a large glass of water to counteract possible dehydration.
• Run your wrists under cold water or splash cold water on your face to stimulate circulation.
• Alternating showers or Kneipp affusions can also boost circulation.
• A brisk walk in the fresh air can help clear your head when feeling light-headed.
• Take a short nap in the afternoon – but be careful: If you sleep for more than 30 minutes during the day, you may feel even more dizzy afterwards.

Drowsiness: when to see the doctor?

If you suffer from a constant feeling of lightheadedness and none of the above self-help measures improve, you should see a doctor to rule out a severe medical condition as the cause.

You should also seek medical advice as soon as possible if you notice the following warning signs:

• nausea and vomiting
• high fever
• Neck stiffness: Pain when bending the head
• sudden or very severe headache
• Drowsiness increases during the day, with difficulty staying awake.
• Signs of paralysis, numbness, vision or speech disorders
• Personality changes, abnormal behaviour or apathy
• seizures

You should tell your doctor if you have recently started a new medication and the constant drowsiness is related to it. Under no circumstances should you stop taking the medication without consulting a doctor!