Daytime drowsiness is a common symptom and most often related to not getting enough sleep. When drowsiness occurs most of the time or causes a person to fall asleep at inappropriate times, quality of life and performance can be affected.

Feeling drowsy during the day is often related to not getting enough quality sleep. However, sometimes this can be a symptom of an underlying disorder.

Morning headaches with drowsiness may be an important clue that you have a potentially more serious disorder.

Are you waking up with headaches?

Yes, I have been waking up with headaches.

No, I don't wake up with headaches.

Now that morning headaches are not an issue, we can move on to some of the more common reasons for feeling very drowsy during the day.

Most people need at least seven hours sleep per night and some need nine hours.

Assuming that you are in bed for at least seven hours with the lights out and television off, the most common cause of daytime drowsiness is poor quality sleep.

Do you think that you have problems sleeping?

Yes, I am having trouble sleeping.

No, I am not having trouble sleeping.

Three of the more common reasons for difficulty falling asleep or staying asleep are insomnia, depression, and sleep apnea. Insomnia is easy to recognize, but diagnosing the other two disorders may be less obvious. For instance, sadness may not be a prominent feature of depression and the person experiencing sleep problems will often not recognize that depression is the problem.

With sleep apnea, the person may wake up many times during the night without being aware of it. Heavy snoring is a predominant feature of sleep apnea. The person with the disorder may not know that they snore, but his or her partner will hear it.

If you suspect that you may have a sleep disorder, contact your doctor.

Even though you think you are in bed for enough hours and getting good quality sleep, it is still quite possible that this is the problem. A common symptom of a sleep disorder is dosing off multiple times during the day.

Do you fall asleep inappropriately or unexpectedly several times per day?

Yes, I fall asleep easily several times per day.

No, I rarely fall asleep during the day.

It can often be difficult to differentiate drowsiness from fatigue. Either or both could be caused by an underactive thyroid (hypothyroidism).

Do you have one or more of these symptoms in addition to feeling drowsy?

• constipation

• difficulty staying warm

• dry skin

• fatigue

• muscle aches

• weight gain

Yes

No

So far you have indicated that you are drowsy during the day, that you do not have difficulty sleeping, and you don't have symptoms suggestive of an underactive thyroid (hypothyroidism).

Many prescription and non-prescription drugs can have drowsiness as a side effect.

Are you taking medications, herbs, or supplements that you think might be making you drowsy?

Yes, I am.

No, I do not think it is something I take.

If the symptoms persist over the next couple weeks, contact your doctor to discuss getting a thyroid blood test.

There may still be another reason for your daytime drowsiness.

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So far you have indicated that you are drowsy during the day and that you do not have difficulty sleeping. Your answers indicate that you may or may not have an underactive thyroid (hypothyroidism).

Many prescription and non-prescription drugs can have drowsiness as a side effect.

Are you taking medications, herbs, or supplements that you think might be making you drowsy?

Yes, I am.

No, I do not think it is something I take.

Even three drinks of alcohol per evening may cause drowsiness in some individuals.

Do you drink three or more alcoholic beverages per day?

Yes, I have at least three drinks per day.

No, I drink two or less per day.

Depression can cause drowsiness. It would be unusual for drowsiness to be the only symptom of depression.

Have you also noted one or more of the following?

• feeling sad or low

• loss of enjoyment in things that you previously liked to do

• blaming yourself for circumstances and events in your life

• difficulty sleeping

• staying in bed for most of the day

Yes, I have had one or more of these symptoms.

No, I have not had one or more of these symptoms.

Your answers do not point to any particular reason for your drowsiness. If this is a recent change that is getting worse or has persisted for more than a month, contact your doctor.

Depression is a possibility. Contact your doctor.

Consider decreasing to one to two drinks per day, or perhaps stopping completely. If you need help controlling alcohol consumption, contact your doctor.

Check with your pharmacist or doctor to see if you are taking anything that may be causing the drowsiness.

Many people with sleep apnea are not aware that they have a sleep disorder. They may think that they sleep well and look for other reasons that they have to fight to stay awake, especially when reading, watching television, or driving. Narcolepsy is another cause of falling asleep inappropriately.

Contact your doctor to investigate whether you may have one of these sleep disorders.

The headaches may be unrelated to your daytime drowsiness, but they could be caused by a neurologic condition or sleep disorder.

Are the headaches accompanied by one or more of the following additional symptoms?

• blurred vision

• problems with memory, speech, or imbalance

• increased head pain when lying down

Yes

No

Morning headaches with drowsiness and no other specific symptoms may indicate that you are having altered breathing during the night with short periods of decreased oxygen supply to the brain.

Contact your doctor for evaluation of possible sleep apnea or a respiratory problem.

Any of these symptoms raise the concern for a serious neurologic disorder.

Contact your doctor immediately.