Can’t keep my eyes open during the day: what causes this beyond ‘not enough sleep’?

Can’t Keep My Eyes Open During the Day: What Causes This Beyond “Not Enough Sleep”

Daytime drowsiness can feel like an overwhelming fog that makes even simple tasks a struggle. While it’s easy to blame “not getting enough sleep,” there are many other reasons your eyelids might droop despite clocking adequate hours in bed. Below, we explore common and less-obvious causes—from breathing problems at night to liver-related issues—and suggest next steps for finding relief.

1. Breathing-Related Sleep Disorders

When your airway partially or fully closes during sleep, your brain must briefly rouse you to resume breathing. These repeated interruptions fragment sleep, leaving you tired by morning.

• Obstructive sleep apnea (OSA)

• Loud snoring, gasping or choking during sleep
• Morning headaches, dry mouth, daytime sleepiness
• Risk factors: overweight, large neck circumference, narrow airway

• Central sleep apnea (CSA)

• Brain fails to send proper signals to breathing muscles
• Less common than OSA; often linked to heart failure or stroke

→ Treatment options include airway pressure devices (CPAP/BiPAP), oral appliances or surgery.

2. Narcolepsy and Hypersomnia

If you find yourself nodding off in the middle of conversations or activities, narcolepsy or idiopathic hypersomnia might be at play.

• Narcolepsy

• Sudden daytime “sleep attacks” lasting minutes to half an hour
• Other features: cataplexy (brief loss of muscle tone), sleep paralysis, vivid hallucinations

• Idiopathic hypersomnia

• Persistent, excessive daytime sleepiness without cataplexy
• Long, unrefreshing naps

→ A sleep specialist can confirm diagnosis via overnight polysomnography and daytime nap tests. Medications and lifestyle changes help manage symptoms.

3. Circadian Rhythm Disorders

Your body’s internal clock (circadian rhythm) regulates the sleep–wake cycle. If it’s out of sync with your daily schedule, you may feel sleepy at odd times.

• Delayed sleep–wake phase disorder

• Naturally late to bed (2–4 a.m.) and late to wake (10 a.m. or later)
• Feels sleepy in the early evening when “normal” bedtime approaches

• Shift work sleep disorder

• Working nights or rotating shifts
• Trouble falling asleep after a shift; excessive sleepiness on duty

→ Bright-light therapy, melatonin at strategic times and good sleep hygiene can reset your clock.

4. Chronic Liver Disease and Cirrhosis

Even if you don’t feel particularly “sick,” liver dysfunction can disrupt sleep architecture and lead to daytime sleepiness. Research shows that people with cirrhosis often experience:

• Altered sleep–wake patterns

• Difficulty falling asleep at night, daytime napping
• Fragmented, non-restorative sleep (Montagnese & Morgan, 1998)

• Hepatic encephalopathy (early stages)

• Mild cognitive slowing, poor concentration, daytime drowsiness
• Toxin buildup (e.g., ammonia) affects brain function

• Sleep–wake inversion

• Sleeping more during the day than at night (Montagnese et al., 2009)

If you’ve been diagnosed with liver disease—or have risk factors like long-term alcohol use, viral hepatitis or fatty liver—ask your hepatologist about managing sleep issues.

5. Electrolyte Imbalances

Severe shifts in your body’s electrolytes can sap your energy and impair brain function. Hyponatremia (low blood sodium) is one example:

• Symptoms of hyponatremia

• Headache, nausea, confusion, fatigue
• In advanced cases: seizures, coma, death (Kim et al., 2008)

• Why it matters in liver disease

• People awaiting liver transplant frequently develop hyponatremia
• Low sodium worsens fatigue and cognitive slowing

If blood tests show low sodium—or you have conditions that predispose you to it—work with your doctor to correct the imbalance safely.

6. Mental Health Conditions

Your mood and mind health directly affect sleep quality and daytime alertness.

• Depression

• Oversleeping (hypersomnia) or trouble sleeping (insomnia)
• Low motivation, persistent sadness, concentration difficulties

• Anxiety

• Racing thoughts at bedtime, early-morning awakenings
• Daytime tension can feel exhausting

→ Cognitive-behavioral therapy (CBT), stress management and, if needed, medication can improve both mood and sleep.

7. Thyroid Dysfunction

Your thyroid gland controls metabolism. Both underactive (hypothyroidism) and overactive (hyperthyroidism) states can disrupt energy levels.

• Hypothyroidism

• Fatigue, weight gain, cold intolerance, slowed thinking

• Hyperthyroidism

• Restlessness, heat intolerance, muscle weakness, difficulty sleeping

A simple blood test (TSH, free T4) can pinpoint thyroid issues, and proper treatment usually restores normal energy levels.

8. Anemia and Nutritional Deficiencies

Low red blood cell counts (anemia) or deficiencies in iron, B12 or folate reduce oxygen delivery to tissues, causing:

• Symptoms of anemia

• Generalized weakness, shortness of breath, pale skin
• Rapid heartbeat, dizziness

• Other key deficiencies

• Vitamin D, magnesium and others can subtly affect energy and mood

A doctor can order appropriate blood tests and recommend supplements or dietary changes.

9. Medication Side Effects

Many prescription and over-the-counter medications list drowsiness as a side effect. Common culprits:

• Antihistamines (allergy meds)
• Antidepressants and antipsychotics
• Opioid painkillers
• Muscle relaxants
• Some blood pressure and seizure medications

Review your medication list with your physician or pharmacist to see if dosage adjustments or alternatives are possible.

What You Can Do Next

1. Keep a sleep diary for 1–2 weeks: record bedtimes, wake times, naps and any nighttime awakenings.
2. Practice consistent sleep hygiene:
   • Stick to a regular sleep schedule, even on weekends
   • Create a cool, dark, quiet bedroom environment
   • Limit screen time at least 1 hour before bed
3. Consider doing a free, online symptom check for
4. Share your sleep diary and any symptom-check results with your healthcare provider.

When to Talk to a Doctor

Daytime sleepiness is sometimes harmless, but it can also signal serious conditions. Seek prompt medical attention if you experience:

• Loud, gasping snoring or witnessed pauses in breathing during sleep
• Sudden “sleep attacks” or muscle weakness (cataplexy)
• Confusion, seizures or fainting spells
• Marked changes in mood or behavior
• Persistent fatigue that affects work, school or safety (e.g., driving)

Your health is too important to ignore persistent daytime drowsiness. A thorough evaluation—including sleep studies, blood tests and a medication review—can uncover treatable causes and help you reclaim energized, alert days.

Remember: if you feel something is wrong, speak to a doctor about any symptoms that could be life threatening or serious.