Drowsiness refers to feeling excessively tired or sleepy, especially at times when a person would not usually need to sleep. There are several reasons that a person may feel drowsy, and drowsiness may lead to other symptoms.

Drowsiness may be a sign of an underlying physical or mental health condition, a side effect of certain medication, or related to certain lifestyle factors.

There are several ways of treating drowsiness, including home treatments, therapies, and medications.

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When a person is drowsy, their mind and body are slower to process and react to information.

Drowsiness causes activity in certain parts of the brain to change, leading to decreased cognitive function, alertness, and overall ability to process and react to information.

When a person is drowsy, they may feel very tired, as if they have not had enough sleep even when this is not the case. Often, people experiencing drowsiness may find that sleep is not refreshing. They may have difficulty taking part in work, conversations, or leisure activities.

Feeling drowsy may lead to other symptoms or issues, such as:

  • confusion or difficulty concentrating
  • excessive daytime sleeping
  • depression or anxiety
  • increased stress
  • difficulty making decisions
  • slower reactions

Accidents, including traffic collisions, caused by drowsiness are common.

The National Highway Traffic Safety Administration (NHTSA) reports that in 2017, around 91,000 crashes reported to the police involved drowsy drivers, which was 1% to 2% of all crashes.

There are many potential causes for drowsiness, ranging from life circumstances to underlying illness. Some of these causes may be short term, while others may be related to chronic health conditions.

Medication

Certain medications can causeTrusted Source drowsiness as a side effect, such as:

This can happen due to several different changes in the body, such as slowing neurons in the brain, reducing blood pressure, or blocking certain chemicals that help a person to feel awake.

If a person is experiencing prolonged drowsiness due to taking a medication, a doctor may be able to adjust the medication or dose to avoid this side effect.

Mental health

Fatigue is a potential symptom of certain mental health conditions, and can often cause drowsiness.

Around 90% of people with a major depressive disorder experience depression fatigue. This can be due to many factors, such as sleep issues, stress, diet, or side effects of medication.

Other mental health conditions may cause fatigue/drowsiness, including:

Life events that cause stress can also lead to fatigue and drowsiness.

Sleep disorders

Sleep disorders often causeTrusted Source fatigue and drowsiness, such as:

Different sleep disorders affect people in different ways by impacting their sleep schedule, how much sleep they get, and the quality of their sleep.

Any of these issues can cause a person to feel drowsy during the day.

Health conditions

Many different health conditions can cause a person to feel drowsy.

Drowsiness and fatigue can be a sign of certain long-term conditions, such as:

Acute conditions like infections, kidney dysfunction, or allergic reactions can also cause drowsiness.

It is important for a person to speak with a doctor if they are experiencing persistent drowsiness.

Treatment for drowsiness will depend on the cause.

A doctor will assess the cause of a person’s drowsiness in order to know how to treat it. This may involve treating an underlying condition, changing medications, or suggesting certain lifestyle changes.

At-home changes to treat drowsiness include:

  • maintaining a regular sleep schedule
  • getting enough exercise
  • eating a balanced diet
  • stress reduction and relaxation techniques, such as meditation and breathing exercises
  • maintaining a moderate weight

Research suggests that certain supplements help to reduce fatigue, including:

If a person is experiencing drowsiness that is stopping them from completing their usual tasks and activities, they should speak with a doctor or healthcare professional.

Drowsiness may be a sign of an underlying issue, and treatment can improve an individual’s quality of life.

If a person experiences sudden or extreme drowsiness, they should seek help immediately. This may be a side effect of a new medication, injury, or another issue that requires urgent attention.

There are several ways for a doctor to assess what may be causing a person to feel drowsy.

They may start by taking a detailed medical history and assessing factors that may affect a person’s sleep, including asking about the individual’s sleeping habits.

A doctor may ask a person to keep a sleep diary for around 2 weeks to track their sleeping habits and drowsiness.

A sleep diary may track the following:

  • sleeping patterns
  • sleep disruptions
  • exercise
  • meditation
  • symptoms
  • use of alcohol and caffeine

Other tests to determine the cause of drowsiness may include:

What is drowsiness a symptom of?

Drowsiness may be a symptom of many different conditions. This includes long-term health conditions or acute conditions, such as injury or allergic reaction, and mental health conditions.

In some cases, drowsiness may happen due to life circumstances rather than being a symptom of an underlying condition.

How to remove drowsiness?

How to get rid of drowsiness will depend on the cause. However, certain steps like maintaining a regular sleep schedule, including at least 7 hoursTrusted Source of sleep per night (for adults), are good steps for reducing feelings of drowsiness.

What are 3 signs of drowsiness?

Three possible signs of drowsiness are:

  • feeling the need to sleep during the day
  • having difficulty with memory or concentration
  • having slow reactions

Resources for healthy sleep

To discover more evidence-based information and resources on the science of healthy sleep, visit our dedicated hub.

Drowsiness can negatively impact a person’s life and stop them from living normally. They may find it difficult to concentrate, interact with others, or carry out activities like driving. Drowsiness may be a sign of an underlying illness, a reaction to medication, or a result of other life circumstances.

A doctor can determine how to treat drowsiness by assessing and treating the cause. Getting enough sleep each night and maintaining a healthy sleep schedule can help reduce drowsiness.