Drowsiness
Sleepiness - during the day; Hypersomnia; Somnolence
Drowsiness refers to feeling more sleepy than normal during the day. People who are drowsy may fall asleep when they do not want to or at times which can lead to safety concerns.
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Do you have trouble falling asleep at night? Or, do you go to sleep, only to wake up a few hours later and stay awake for hours at night? Well, let's today talk about insomnia. Your sleep-wake cycle is a delicate pattern run by something called circadian rhythms. These rhythms are physical, mental, and behavioral changes in your brain that roughly follow a 24-hour cycle. Your daily and nightly habits, many you learned as a child, may affect your circadian rhythms and how well you sleep at night. Poor sleep or lifestyle habits that may cause insomnia include going to bed at different times each night, daytime napping, and a poor sleeping environment such as too much noise or light. Spending too much in time in bed while you're awake can change your sleep patterns too. Likewise, working evenings or night shifts and not getting enough exercise can affect your sleep. People who use alcohol or recreational drugs may have trouble sleeping. Heavy smoking and drinking too much caffeine can also cause insomnia. And, even using some types of sleep medications a lot can cause you to lose sleep. Medical problems can cause insomnia too. People with anxiety disorders, bipolar disorder, thyroid disease, depression, and chronic pain problems may have trouble going to sleep or staying asleep. So, what do you do about insomnia? Well, it's important to remember that not everyone needs 8 hours of sleep every night. Some people do just fine on 6 hours of sleep, while others need much more. If you need more sleep, your doctor will probably ask about any medications you're taking, your drug or alcohol use, and your medical history. Spend some time thinking about your lifestyle and sleep habits. It's best to avoid caffeine and alcohol at night. If you don't exercise, starting regular exercise might help you sleep better. If you're depressed or anxious, talk to your doctor to see if relaxation techniques can help, if medication might be helpful, or if seeing a mental health provider is best. If you're suffering from bouts of insomnia, take heart. Most people can return to more normal sleep patterns when they make simple changes in their lifestyle or habits.
Considerations
Excessive daytime sleepiness (without a known cause) may be a sign of a sleep disorder.
Depression, anxiety, stress, and boredom can all contribute to excessive sleepiness. However, these conditions more often cause fatigue and apathy.
Causes
Drowsiness may be due to the following:
- Long-term (chronic) pain
- Diabetes
- Having to work long hours or different shifts (nights, weekends)
- Insomnia and other problems falling or staying asleep
- Changes in blood sodium levels (hyponatremia or hypernatremia)
- Medicines (tranquilizers, sleeping pills, antihistamines, certain painkillers, some psychiatric drugs)
- Not sleeping long enough
- Sleep disorders (such as sleep apnea and narcolepsy)
- Too much calcium in your blood (hypercalcemia)
- Underactive thyroid (hypothyroidism)
Home Care
You can relieve drowsiness by treating the cause of the problem. First, determine whether your drowsiness is due to depression, anxiety, boredom, or stress. If you are not sure, talk with your health care provider.
For drowsiness due to medicines, talk to your provider about switching or stopping your medicines. But, DO NOT stop taking or change your medicine without first talking to your provider.
Do not drive when drowsy.
What to Expect at Your Office Visit
Your provider will examine you to determine the cause of your drowsiness. You will be asked about your sleep patterns and health. Questions may include:
- How well do you sleep?
- How much do you sleep?
- Do you snore?
- Do you fall asleep during the day when you do not plan to nap (such as when watching TV or reading)? If so, do you awake feeling refreshed? How often does this happen?
- Are you depressed, anxious, stressed, or bored?
- What medicines do you take?
- What have you done to try to relieve the drowsiness? How well did it work?
- What other symptoms do you have?
Tests that may be done include:
- Blood tests (such as a CBC and blood differential, blood sugar level, electrolytes, calcium, and thyroid hormone levels)
- CT or MRI scan of the head
- Electroencephalogram (EEG)
- Sleep studies
- Urine tests (such as a urinalysis)
Treatment depends on the cause of your drowsiness.
References
Avidan AY. Sleep and its disorders. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 101.
Mansukhani MP, Kolla BP, St. Louis EK. Sleep disorders. In: Kellerman RD, Rakel DP, Heidelbaugh JJ, Lee EM, eds. Conn's Current Therapy 2023. Philadelphia, PA: Elsevier 2023:794-809.
Sharafkhaneh A, Hirshkowitz M. Evaluating sleepiness and fatigue. In: Kryger M, Roth T, Goldstein CA, Dement WC, eds. Principles and Practice of Sleep Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 207.
Version Info
Last reviewed on: 7/8/2023
Reviewed by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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