Drowsiness: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Drowsiness?
A primary care doctor usually starts the search for the cause of drowsiness, which is feeling sleepier than normal during the day. A sleep medicine doctor, a doctor who treats sleep disorders, may take over if a sleep problem is suspected. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is drowsiness?
Drowsiness means feeling more sleepy than normal during the day. People who are drowsy may fall asleep when they do not want to, which can lead to safety concerns. Other names for it include sleepiness during the day, hypersomnia, and somnolence. Doctors say excessive daytime sleepiness is different from feeling tired all the time. Excessive daytime sleepiness with no known cause may be a sign of a sleep disorder.
Symptoms
With hypersomnia, you may:
- Nap regularly during the day.
- Fall asleep during the day.
- Still sleep for long hours at night.
Some other conditions come with extra signs. Narcolepsy can cause a need to sleep anywhere, sometimes without warning. Sleep apnea can cause loud snorting and snoring at night. Restless legs syndrome can cause an unusual feeling in the legs, mostly at night. Depression can bring low mood and little interest in things.
Causes and who gets it
Drowsiness can have many causes. These include:
- Long-term pain.
- Diabetes.
- Long work hours or shift work, such as nights and weekends.
- Insomnia and other problems falling or staying asleep.
- Not sleeping long enough.
- Sleep disorders such as sleep apnea and narcolepsy.
- An underactive thyroid, called hypothyroidism.
- Changes in blood sodium levels.
- Too much calcium in the blood.
- Medicines such as tranquilizers, sleeping pills, antihistamines, certain painkillers, and some psychiatric medicines.
Some other medicines, drinking too much alcohol, and taking drugs can also cause it. Depression, anxiety, stress, and boredom can add to sleepiness, but they more often cause fatigue and apathy. In idiopathic hypersomnia, a person sleeps for long periods and wakes up confused or irritable and not refreshed. There is no known cause for it.
How doctors diagnose it
Your provider will examine you and ask about your sleep patterns and health. Questions may cover how well and how much you sleep, whether you snore, and what medicines you take. You may be asked if you fall asleep during the day when you do not plan to nap. A doctor may also ask you to keep a diary of when you sleep.
Tests that may be done include blood tests, such as blood sugar and thyroid hormone levels. Other tests include a CT or MRI scan of the head, an EEG, sleep studies, and urine tests. Your doctor may refer you to a doctor who specializes in sleep disorders.
Treatment
Treatment depends on the cause of your drowsiness. You can relieve drowsiness by treating the cause of the problem. Treatment may include medicine to help keep you awake.
If a medicine is the cause, talk to your provider about switching or stopping it. Do not stop or change a medicine without first talking to your provider, and follow your doctor's instructions. Changing sleep habits may not cure the problem, but it might help you feel better.
- Go to bed at the same time every night.
- Avoid alcohol and caffeine.
- Create a peaceful sleeping environment.
- Avoid working late into the night.
When to see a doctor
See a doctor if you often fall asleep during the day or your sleepiness is affecting your life. Do not drive when drowsy. Call 911 or go to the emergency room if a person is hard to wake, or has a change in mental status such as confusion or unusual behavior. Also call 911 for a child with a lack of alertness or a diminished response.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can review your medicines and sleep habits, order basic tests, and refer you to a sleep specialist.
Common questions
Is drowsiness the same as being tired?
No, excessive daytime sleepiness is different from feeling tired all the time. People with it may nap often or fall asleep during the day.
Can medicines cause drowsiness?
Yes, some medicines can cause drowsiness. Talk to your provider before you stop or change any medicine.
Is it safe to drive when drowsy?
No, do not drive when you are drowsy. Drowsy people may fall asleep when they do not want to, which can lead to safety concerns.
Can drowsiness be a sign of a sleep disorder?
Yes, it can be a sign of a sleep disorder. Sleep apnea and narcolepsy are examples.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
