Comfort and side effects

Still Tired on CPAP? Why and What to Do

If you still feel tired on CPAP, the most common reasons are not using it long enough each night, mask leak, a high AHI, or another sleep problem. Check your data, aim for all night use, and talk to your doctor if sleepiness continues.

Signs

  • Daytime sleepiness despite using CPAP
  • Falling asleep while reading or watching TV
  • Morning tiredness
  • Poor concentration

Common causes

Not enough hours
AASM says CPAP works best when used all night, every night, including naps.
Mask leak or high AHI
Leaks reduce the pressure reaching your airway. A rising AHI can mean therapy is not controlling events.
Central apneas
ResMed notes a rising AHI can be a sign of central sleep apnea.
Residual sleepiness
A European study found 28.2% still had an Epworth score above 10 at follow-up on CPAP.
Other causes
Insufficient sleep, other sleep disorders, depression and medicines can all cause tiredness.

Fixes to try, easiest first

  1. Use CPAP all night, every night

    Aim to wear CPAP for your whole sleep time, including naps.

  2. Get enough sleep

    Make sure you are allowing enough time in bed. The AASM suggests a bedtime early enough for at least 7 to 8 hours of sleep, and getting up at the same time every day.

  3. Check your leak and AHI

    Look at your app for leak and events per hour. ResMed says an AHI under 5 is considered normal.

  4. Fix mask problems

    Refit your mask and fix leaks.

  5. Limit alcohol and sedatives

    Alcohol and some medicines can make apnea worse.

  6. See your doctor with your clinician

    If you are still sleepy after several weeks of good use, ask your doctor to look for other causes.

When to call your doctor

Talk to your doctor if you are still sleepy after several weeks of using CPAP most of the night. Do not drive if you feel drowsy. Call your provider if your AHI rises over several nights or your app shows central apneas.

Mask types this applies to

Nasal maskNasal pillows maskFull face mask

Frequently asked questions

How long does it take to feel better on CPAP?

Some people feel better in days, others take weeks. Using CPAP for most of the night every night speeds it up.

Why am I still tired if my AHI is low?

Short sleep time, other sleep disorders, medicines and mood can all cause tiredness. Your doctor can check.

Can CPAP make me more tired at first?

Some people sleep poorly during the first weeks while adjusting. This usually improves.

Sources

Last reviewed October 11, 2026. How we research · Report an error

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