Why Am I Always Sleepy?

Even if you are routinely getting a good night's sleep, it's possible to feel always sleepy during the day.

There are many potential underlying causes for feeling constantly tired, including:

• Lifestyle factors
• Medical conditions
• Sleep disorders
• Mental health conditions
• Chronic stress
• Nutritional deficiencies

This article looks at 27 possible reasons why you might feel sleepy during the day, even if you sleep well at night, and things you can do to lessen daytime tiredness.

Always Feeling Sleepy: Lifestyle Factors

Different aspects of your lifestyle can have a big impact on your daytime alertness and energy levels. Among the factors that you may want to discuss with a healthcare provider are:

• Diet
• Dehydration
• Sleep habits
• Sedentary lifestyle
• Overexertion
• Your work schedule
• Stress levels

Diet

Your body gets most of its energy from food. Failing to eat a balanced diet or skipping meals can lead to poor nutrition. This may contribute to feeling tired during the day.

Some diet-related causes of excessive sleepiness include:

• Vitamin and mineral deficiencies, especially of iron, vitamin B12, and vitamin D
• Changes in your blood sugar level that limit your body's ability to transport energy to its cells
• Excessive alcohol consumption
• Consuming too much caffeine

Simple dietary changes and/or nutritional supplements may be all that's needed to help you stop feeling sleepy.

Dehydration

When you don't get enough water or other liquids, you can become dehydrated. Around 50% to 60% of your body weight consists of water. Sweating, urinating, being in the heat, and being sick all deplete the water in your body.

When you don't get enough fluids on a regular basis, you may feel more tired than usual and low on energy. While there is no official recommendation on how much water and other fluids you should drink, the general thinking is eight 8-ounce glasses per day; however, this does not apply to everybody.

Your healthcare provider can advise you on how much liquid you should be drinking and if dehydration could be the reason you're so beat.

Poor Sleep Habits

It may seem obvious, but it's possible you're tired during the day because you're not getting enough sleep. Here are some common sleep-stealing culprits:

• Trying to sleep in an environment that's hot, noisy, or uncomfortable
• Lacking a bedtime routine designed to help you fall asleep
• Exercising within a few hours of bedtime
• Napping late in the day
• Failing to get the proper amount of rest needed in your stage of life

Getting into a regular sleep routine and creating a pleasant sleeping environment may help you feel less sleepy during the day.

Inactive Lifestyle

Being sedentary—not getting much physical activity—makes you more likely to have restless, poor-quality sleep. Snoring and short pauses in breathing may contribute to the problem. Other factors of inactivity that can contribute to sleep problems include:

• Higher rates of depression
• Increased rates of metabolic syndrome
• Screen time and exposure to light from your devices

Research suggests that getting more physical activity can help to improve your sleep quality.

One study followed 41 people, some of whom engaged in at least 150 minutes of moderate to vigorous exercise each week for six months. Those in this exercise group reported less insomnia, depression, and anxiety than those who did not exercise.

Overexertion

Exercising too much or overexerting yourself in other ways can leave your body too depleted to recover overnight. This can lead you to feel tired and unmotivated or make it hard for you to sleep well. Other symptoms that can go along with overexertion include:

• A decline in your ability to perform at work and at home
• Depression or mood swings
• Sore, heavy limbs
• Overuse injuries
• Getting sick more often
• Anxiety
• Unintended weight loss

Cutting back on exercise, or giving yourself a week or two off to rest and recover, may help you feel less sleepy during the day.

Stress

Psychological stress can greatly impact how much and how well you sleep. Even worse, the lack of sleep can make you feel even more stressed. A survey of 1,950 adults by the American Psychological Association found that:

• 43% of adults said stress had kept them awake at night in the prior month
• 21% reported feeling more stressed after not getting enough sleep
• Among those with higher stress levels, 45% said losing sleep increased their stress level
• 37% reported being tired or fatigued due to stress

A 2020 study found that getting a good night's sleep helped people maintain positive emotions in the face of a stressful event and allowed them to feel more joy from positive experiences.

Lowering your stress levels or learning how to manage your stress better may make you feel less tired. If you're unable to do this on your own, talk to your healthcare provider.

Feeling Tired All the Time: Common Medical Causes

Fatigue, general weakness, and feeling sleepy are symptoms associated with many medical conditions. Your symptoms of daytime sleepiness may be related to underlying causes that include:

• Anemia
• Autoimmune disease
• Cancer
• Chronic fatigue syndrome
• Chronic obstructive pulmonary disease (COPD)
• Depression
• Diabetes
• Fibromyalgia
• Heart disease
• Infection
• Menopause
• Pregnancy
• Thyroid disease

These conditions affect your energy levels and lead to fatigue for different reasons. Your energy level also may be affected by your treatment as is often the case with cancer and chemotherapy.

Anemia

Anemia is a condition that causes you to have fewer red blood cells or a loss of function in those that you have. This interferes with the blood cells' ability to deliver oxygen to all of the organs in your body. Common symptoms include:

• Feeling weak or tired
• Headaches
• Problems concentrating or thinking
• Irritability
• Loss of appetite
• Numbness and tingling of hands and feet

The most common type of anemia is caused by an iron deficiency. There are other causes, ranging from inherited blood disorders and chronic illness to temporary conditions like pregnancy.

A healthcare provider can diagnose most forms of anemia through blood tests. Treatments can vary from simple changes in your diet to more serious procedures like a red blood cell transfusion.

Autoimmune Disease

In autoimmune diseases, your immune system mistakenly attacks the processes in your own body. This can lead to tissue damage and chronic inflammation. Some autoimmune diseases include:

• Rheumatoid arthritis
• Lupus
• Multiple sclerosis
• Sjögren's syndrome
• Inflammatory bowel disease

These conditions often lead to fatigue. They may interfere with oxygen and nutrient supply to the body and disrupt your metabolism and nervous system. They can also result in imbalances in cytokines, which play a role in regulating mood and sleep.

Treatment for autoimmune diseases often includes medication to manage symptoms and better control the immune system condition.

Cancer

More than 80% of people with cancer experience cancer-related fatigue. Extreme fatigue that doesn't get better with rest is often an early sign of cancer. Many factors can contribute to the fatigue and weakness of cancer, including:

• Low blood counts or disturbed electrolytes, the key minerals in your body
• Altered hormone levels
• Altered cytokine and inflammation levels
• Changes caused by cancer that affect how cells function

Cancer treatments can also cause fatigue. These treatments may include:

• Chemotherapy
• Immunotherapy
• Targeted therapy
• Radiation
• Surgery (during the recovery process)

Your medical team should be able to help you fight feeling sleepy all the time, so be sure to bring it up.

Chronic Fatigue Syndrome

Chronic fatigue syndrome (myalgic encephalomyelitis or ME/CFS) causes extreme fatigue. It doesn't get better with rest and often involves flu-like symptoms and a "brain fog" type of cognitive dysfunction.

The fatigue for people with ME/CFS gets worse even with small amounts of exertion. This leads to serious day-to-day impacts for people living with ME/CFS.

The potential causes of ME/CFS aren't known. In some people, the disease may have developed in response to infection or chronic stress. There also may be an autoimmune response involved. Research suggests a number of possible causes of fatigue in ME/CFS. They may involve:

• Long-term infection
• Sleep disorders and disruption
• Cytokine problems and inflammatory activity

People are diagnosed with ME/CFS after severe, unexplained fatigue lasts for at least six months. Even then, ME/CFS is hard to pinpoint. It can take a long time to come to a diagnosis.

The disorder is treated with a drug combination of antivirals and antidepressants. Specific symptoms are treated with sleep medications and other drugs or nutritional supplements. Cognitive behavioral therapy is also a common, though controversial, ME/CFS treatment.

Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) causes wheezing, shortness of breath, and excess mucus in the airways. These factors can make it hard to breathe. The disease gets worse over time and is especially common in current or past smokers.

It's long been thought that difficulty breathing leads to fatigue. Some research suggests a more complex situation because fatigue doesn't always seem tied to any effort needed to breathe.

Once the link is better understood, it should become easier to manage COPD-related fatigue. For now, the primary focus is on breathing exercises and healthy lifestyle habits.

Depression

Depression is a mood disorder. It often brings feelings of sadness and loss of interest in activities, but it also causes physical symptoms such as fatigue.

Daytime sleepiness may be due to insomnia or other sleep problems that often occur with depression. Research suggests that fatigue, insomnia, and problems with concentration may be warning signs of depression.

Certain biochemical changes in depression are similar to those seen in ME/CFS. This may one day explain fatigue as a symptom of depression, but also why people with ME/CFS often have it.

Depression is typically treated with antidepressant medications. If you believe you may be depressed, it's important to talk to your healthcare provider and get proper treatment.

Diabetes

Fatigue is extremely common in people with diabetes. In 2018, some researchers even made a case for a new condition called "diabetes fatigue syndrome."

Possible reasons for this fatigue include:

• Low blood sugar levels
• Hormonal imbalance
• Side effects of treatment
• Overlapping health conditions
• Diet and other lifestyle factors

Diabetes is generally treated with medications that stabilize blood-sugar levels and/or insulin.

Fibromyalgia

Fibromyalgia is a chronic pain condition. It's caused by dysfunction in the central nervous system, which heightens sensitivity and turns harmless sensations into pain or allodynia.

Fatigue is also a key symptom of fibromyalgia. This fatigue may be due to biochemical changes, inflammation, sleep disorders, and sleep disruptions.

Some of these causes are similar to those seen with ME/CFS and depression. Fibromyalgia treatment often includes antidepressant drugs, anti-seizure drugs, and low-impact exercise.

Heart Disease

If you have fatigue that's new and constant, it may be an early warning sign of heart failure or, less often, coronary artery disease. These conditions limit the amount of oxygen-rich blood that gets to your muscles or to the heart itself.

Your body needs to supply the heart and brain well. So it limits the blood sent to less key organs, such as your limbs. That leaves them with less oxygen. This will sap your energy and cause fatigue.

Other symptoms of weak heart muscles and heart failure include:

• Shortness of breath
• An irregular, fast, or pounding heartbeat
• Swollen legs and feet

Treatment for heart failure usually relies on medication. These heart drugs include beta-blockers, ACE inhibitors, and diuretics that help the body to remove excess fluid. Implanted devices and surgeries also may be used, such as a defibrillator, valve replacement, or heart transplant.

Coronary artery disease involves plaques that clog your arteries. Common symptoms are the same as those for heart failure, with added chest pain or discomfort. Treatments include statin and beta-blocker drugs, angioplasty, and sometimes coronary artery bypass surgery.

Infections

It is common to feel tired when you're sick. Fatigue frequently accompanies infectious illnesses such as:

• COVID-19
• Influenza
• Mononucleosis (mono)

Tiredness caused by an infection usually clears up with the illness. Depending on the source and severity, it may be treated by antibiotics, antiviral medications, symptom management, or simply time and rest.

In some cases, though, tiredness lingers well after the illness itself is gone. This is sometimes referred to as post-viral fatigue or persistent fatigue after infection. With COVID-19, this is often called post-COVID syndrome, long COVID, or long-haul COVID.

The Epstein-Barr virus (EBV), which causes mononucleosis, is known to linger or reactivate later and cause fatigue, among other symptoms. It's implicated in ME/CFS and several autoimmune diseases.

Treatment for post-viral exhaustion depends on the virus involved, the full range of symptoms, and what damage may have been left behind by the original illness. Common treatments are anti-viral medications and immunotherapy.

Menopause

The transition to menopause, starting with perimenopause and continuing into the early post-menopausal stage, is associated with fatigue along with:

• Hot flashes
• Night sweats
• Menstrual irregularities
• Mood swings
• Headaches
• Cognitive problems

Tiredness in menopause may be related to sleep disruptions caused by hot flashes and night sweats. Other causes could be related to hormonal changes, aging, and stresses associated with this time of life. Some research points to a complex relationship between menopausal fatigue and stress.

Menopause isn't a disease that needs to be treated. However, you do have options for managing symptoms and making yourself more comfortable. They include:

• Hormone replacement therapy (HRT)
• SSRI antidepressants such as Paxil (paroxetine) or Effexor (venlafaxine) for hot flashes, night sweats, and mood issues
• Exercise, including walking, swimming, and yoga

Pregnancy

When you're pregnant, a lot of extra demands are placed on your body. This can lead to feeling tired. Fatigue is most common and typically most severe in the first and third trimesters, but some people are exhausted throughout their pregnancies. Causes of pregnancy-related fatigue include:

• Energy needed to create the placenta and nourish the baby
• Increased metabolism
• Hormonal changes
• Low blood sugar
• Low blood pressure
• Digestive changes
• Stress
• Sleep disruption due to pain, needing to urinate during the night, or (later on) the baby's activity

Some research indicates that resistance-training exercise may help alleviate pregnancy fatigue. Other ways to cope with it include:

• Getting lots of rest
• Scaling back on activities or responsibilities
• Eating a balanced diet
• Staying active without pushing yourself too hard

If your fatigue suddenly increases at any point during your pregnancy, it could be a sign of trouble. Some possible causes include depression, iron-deficiency anemia, or gestational diabetes.

Thyroid Disease

An imbalance of your thyroid hormones can cause tiredness, and that's true whether your levels are high (hyperthyroidism) or low (hypothyroidism). Your thyroid gland, which sits at the front of your neck, produces several hormones that regulate your metabolism and have a major effect on your health.

Hyperthyroidism

In hyperthyroidism, all the processes in your body are sped up. This causes anxiety, a racing heart, shaking hands, unintended weight loss, and sleep problems. It can also lead to excessive sweating, which can disrupt your sleep. These sleep issues can leave you tired during the day.

Early in hyperthyroidism, you may have a lot of energy. It's not sustainable, though, and as the disease goes on, your body can become depleted and leave you fatigued.

Treatments for hyperthyroidism include:

• Drugs such as Tapazole (methimazole) or beta blockers
• Radioactive iodine, which lowers hormone levels by targeting hormone-producing cells
• Surgical removal of part or all of the thyroid gland

Surgery and iodine treatments typically drop your thyroid hormone levels to low levels. This means you'll then need to take synthetic hormones to maintain a healthy level.

Hypothyroidism

In hypothyroidism, all the body's processes are slowed down, and that slowdown itself causes fatigue. Other symptoms include:

• Weight gain in spite of a decrease in appetite
• Becoming easily chilled
• High blood pressure
• High cholesterol
• Dry skin and brittle nails
• Concentration and memory problems
• Depression

Hypothyroidism is treated with synthetic thyroid hormones.

Daytime Sleepiness Causes: Sleep Disorders

Excessive daytime sleepiness and fatigue are the primary symptoms of sleep disorders. These disorders may include:

• Circadian rhythm disorders
• Insomnia
• Kleine-Levin syndrome
• Narcolepsy
• Restless legs syndrome
• Sleep apnea

If your healthcare provider suspects you have a sleep disorder, they may ask you to keep a log of how long and how well you sleep. They may send you for a sleep study, known as polysomnography. Many sleep disorders can be successfully treated once they're identified.

Circadian Rhythm Disorders

Various circadian rhythm disorders can leave you feeling too sleepy during the day. The circadian rhythm is your body's natural clock and it helps to coordinate your activities based on when it's light and dark in your environment. If your internal timing is misaligned, you may find yourself with excessive daytime sleepiness. Six common circadian rhythm disorders are:

• Advanced sleep phase syndrome: The distinguishing feature is falling asleep and waking up earlier than you want, usually by about three hours.
• Delayed sleep phase syndrome: Similar to insomnia, this causes difficulty falling asleep and makes it extremely hard to wake up.
• Irregular sleep-wake rhythm: This occurs when the circadian rhythm becomes completely disconnected from the natural day-night cycle. Sleep is fragmented, with short spells scattered throughout the day.
• Jet lag: A temporary rhythm disorder associated with travel across several time zones. To adjust, it may take one day for every time zone you crossed.
• Non-entrained (non-24) disorder: This usually occurs in visually impaired people. The sleep cycle is typically a little longer than average and thus becomes more out of sync every day.
• Shift-work sleep disorder: Poor sleep is caused by working at night and sleeping during the day. This can lead to increased accidents and possibly a higher risk of some forms of cancer.

Effective treatments for circadian rhythm disorders include light therapy, melatonin, sedatives or stimulant medications, and behavioral changes that improve your sleep habits.

Insomnia

Probably the best-known sleep disorder, insomnia can make it hard for you to fall asleep, stay asleep, or get quality sleep. Just about everyone has an occasional bout of insomnia. For some, it's a chronic problem that leaves them feeling tired all the time.

Insomnia can be caused by a combination of factors. They include:

• Genetics
• Environment
• Working at odd hours or keeping an unusual sleep schedule
• Caffeine, nicotine, and other use of stimulants
• Alcohol and other depressants
• Illegal drugs
• Being sedentary
• High stress levels
• Too much light exposure (such as from screens) close to bedtime

Treatments for insomnia include:

• Cognitive behavioral therapy to improve sleep habits
• Lifestyle changes
• Sedative medications
• Light therapy

Kleine-Levin Syndrome

Although quite rare, Kleine-Levin syndrome is a condition that may affect young adults, especially men. It can cause recurrent episodes of excessive sleepiness. These episodes can last for days, weeks, or even months at a time. The level of being tired can be incapacitating.

This syndrome often interferes with school attendance and basic daily functions. Some of the symptoms may include:

• Hallucinations
• Hypersexual or compulsive behaviors
• Binge eating
• Cognitive and mood disturbances

The only treatments thought to be beneficial in Kleine-Levin syndrome are lithium and carbamazepine to help shorten episodes, and stimulants to alleviate fatigue.

Narcolepsy

In narcolepsy, the body is unable to regulate its sleep patterns. Sleep may suddenly occur when you're awake while elements of wakefulness may interrupt sleep. Narcolepsy is characterized by "attacks" of drowsiness that may cause you to doze off for short periods at unexpected times.

Another major symptom of narcolepsy is cataplexy. This is the sudden loss of voluntary muscle control often associated with an emotional response such as surprise or laughter. In a mild instance, your knees may buckle or your jaw will hang open. A more severe episode means you may collapse onto the floor and be unable to move for several minutes.

Other symptoms of narcolepsy include:

• Vivid and often alarming hallucinations while falling asleep or waking up
• Recurring episodes of sleep paralysis, with the sense you are unable to move
• Frequent awakenings at night
• Routine actions done during sleep attacks but with no memory of it afterward

The daytime sleepiness associated with narcolepsy is sometimes treated with stimulants, such as:

• Ritalin
• Provigil
• Nuvigil

The drug Xyrem (sodium oxybate) treats both fatigue and cataplexy. Tricyclic antidepressants and SSRIs may help with cataplexy, hallucinations, sleep paralysis, and overnight sleep disruptions.

Restless Legs Syndrome

Disorders that cause excessive movements during sleep can disrupt your sleep and leave you tired the next day. The most common of these conditions is restless legs syndrome (RLS).

This disorder causes an uncomfortable sensation in the legs coupled with the urge to move. It often develops in the evening as you are lying down to rest and is relieved when you move.

A related condition called periodic limb movement syndrome (PLMS) involves sudden jerking movements that occur during sleep. These may be repetitive, disturbing your sleep and potentially that of your bed partner.

Drugs commonly prescribed for RLS include:

• Anti-seizure medications: Neurontin (gabapentin), Lyrica (pregabalin)
• Dopamine agonists: Requip (ropinirole), Mirapex (pramipexole), Neupro patch (rotigotine)
• Benzodiazepines: Klonopin (clonazepam) in severe cases

Other treatments may include:

• Regular exercise
• Good sleep habits
• Avoiding caffeine
• Using heat, cold, or massage to relieve leg discomfort
• Massage, acupuncture, or relaxation techniques
• Stress reduction or management
• Iron supplements

Sleep Apnea

Sleep apnea is a condition in which your breathing pauses partially or completely while you sleep. It can occur dozens of times an hour or even hundreds of times a night. It's common for these pauses to be followed by a loud snort and brief awakening as you gasp for air.

With each episode, you shift briefly into lighter stages of sleep. You may wake completely and fall back asleep without even remembering it. The frequently disrupted sleep leaves you tired. Other symptoms of sleep apnea include:

• Snoring
• Dry mouth and sore throat in the morning
• Teeth grinding (bruxism)
• Morning headaches
• Sexual dysfunction
• Frequent nighttime urination

Treatment for sleep apnea includes:

• Using a CPAP (continuous positive airway pressure) machine or other types of PAP while sleeping
• Dental devices
• Surgery to correct problems that interfere with breathing, such as large tonsils, unusually small jaw and overbite, or a deviated nasal septum

Medications That Cause Drowsiness

Drowsiness and fatigue are common side effects of medications. Your healthcare provider will likely look into what medications you're taking if you are always sleepy during the day. Drugs that can make you tired include:

• Analgesics: Painkillers including opioids such as Vicodin (hydrocodone-acetaminophen), OxyContin (oxycodone)
• Anticonvulsants: Seizure prevention drugs such as Neurontin (gabapentin) and Lyrica (pregabalin)
• Antidepressants: Tricyclics and SSRIs/SNRIs including Elavil (amitriptyline), Prozac (fluoxetine), Cymbalta (duloxetine)
• Antiemetics: Drugs for nausea, vomiting, and motion sickness such as Dramamine (dimenhydrinate), Anzemet (dolasteron), Zyprexa (olanzapine), Reglan (metoclopramide)
• Antihistamines: Allergy medications including Zyrtec (cetirizine), Claritin (loratadine), Benadryl (diphenhydramine)
• Antipsychotics: Drugs for schizophrenia, psychosis in bipolar disorder, depression, and Alzheimer's disease including Abilify (aripiprazole), Risperdal (risperidone), Seroquel (quetiapine)
• Benzodiazepines: Tranquilizers and sedatives such as Librium (chlordiazepoxide), Valium (diazepam)
• Blood pressure drugs: Diuretics, ARBs, calcium channel blockers, beta-blockers including Lasix (furosemide), Avapro (irbesartan), Calan (verapamil HCL), Toprol-XL (metoprolol succinate)
• Muscle relaxants: Including Soma (carisoprodol), Lorzone (chlorzoxazone), Flexeril (cyclobenzaprine)
• Sedatives: Non-benzodiazepine sedative/hypnotics such as Ambien (zolpidem), Sonata (zaleplon), Lunesta (eszopiclone)
• Statins: Especially fat-soluble drugs including Lipitor (atorvastatin), Mevacor (lovastatin), Vytorin (ezetimibe/simvastatin), Zocor (simvastatin)
• Steroids: Used for inflammation, allergies, skin diseases, certain cancers, and after organ transplants. Some may cause insomnia, including prednisolone, methylprednisolone, dexamethasone

Summary

Feeling tired and sleepy during the day can result from certain illnesses, such as diabetes, heart disease, or an autoimmune disorder. Many cases of fatigue are also related to dehydration, specific sleep disorders, or chronic conditions such as chronic fatigue syndrome.

In addition to getting treatment for an underlying health condition, lifestyle changes such as eating more fruits and vegetables, getting moderate exercise, and practicing good sleep hygiene may ease daytime sleepiness.

Start by talking to your healthcare provider. A routine physical can identify many treatable causes of fatigue, such as iron or vitamin D deficiencies, thyroid disorders, and diabetes. A sleep study can rule out a sleep disorder.