Why Oxygen drops can be higher on some nights

Some factors directly push Oxygen drop (or O₂ drops) up. Others are worth journaling because they change sleep quality and make nights less comparable.

If your O₂ drops are higher on some nights, the goal is not to guess. The goal is to look for patterns. Start with the factors most likely to matter, then use the journal to capture the rest.

High-impact factors to watch

Factor :

More deeper sleep

What the evidence suggests

During deeper sleep (or REM* sleep), dreaming is most common and breathing muscles become more relaxed. The airway is more prone to collapse, and breathing events are often longer and more desaturating¹.

*REM: Rapid Eye Movement.

Why log it

Nights with more deep sleep can look worse even when nothing else changed.

Factor :

Back sleeping

What the evidence suggests

Breathing events are often more frequent or more severe on the back^2,3.

Why log it

If you have persistent snoring or O₂ drops while sleeping on your back, you may wish to investigate tools to prevent or reduce back sleeping.

Factor :

Alcohol before bed

What the evidence suggests

Alcohol relaxes airway muscles and is linked to worse sleep-breathing metrics and lower oxygen during sleep⁴.

Why log it

It is one of the easiest modifiable triggers to spot.

Factor :

Congestion or illness

What the evidence suggests

Blocked nasal breathing and nighttime congestion can make sleep breathing harder⁵.

Why log it

It helps separate a rough sick night from your normal baseline.

Other useful context to journal

Some influences are less straightforward, but still worth tracking because they can change how comparable one night is to another:

Benzodiazepine -based sedatives can also worsen obstructive sleep apnoea (OSA)⁶.
Late or heavy meals may worsen reflux⁷.
Late caffeine can disrupt sleep even when taken 6 hours before bed⁸.

You do not need to log everything forever. Start with the factors that change the most for you. That is usually enough to make the data easier to understand.

What to remember

When you capture the context, higher O₂ drops stop feeling random. Over time, the pattern becomes easier to explain – and easier to act on.

References

Bonsignore MR, Mazzuca E, Baiamonte P, Bouckaert B, Verbeke W, Pevernagie DA. REM sleep obstructive sleep apnoea. Eur Respir Rev. 2024;33(171). doi:10.1183/16000617.0166-2023
Martinot JB, Le-Dong NN, Tamisier R, Bailly S, Pépin JL. Determinants of apnea-hypopnea index variability during home sleep testing. Sleep Med. 2023;111:86-93. doi:10.1016/j.sleep.2023.09.002
Landry SA, Beatty C, Thomson LDJ, et al. A review of supine position related obstructive sleep apnea: Classification, epidemiology, pathogenesis and treatment. Sleep Med Rev. 2023;72:101847. doi:10.1016/j.smrv.2023.101847
Kolla BP, Foroughi M, Saeidifard F, Chakravorty S, Wang Z, Mansukhani MP. The impact of alcohol on breathing parameters during sleep: A systematic review and meta-analysis. Sleep Med Rev. 2018;42:59-67. doi:10.1016/j.smrv.2018.05.007
McNicholas WT. The nose and OSA: variable nasal obstruction may be more important in pathophysiology than fixed obstruction. Eur Respir J. 2008;32(1):3-8. doi:10.1183/09031936.00050208
Ragnoli B, Pochetti P, Raie A, Malerba M. Comorbid Insomnia and Obstructive Sleep Apnea (COMISA): Current Concepts of Patient Management. Int J Environ Res Public Health. 2021;18(17):9248. doi:10.3390/ijerph18179248
Badillo R, Francis D. Diagnosis and treatment of gastroesophageal reflux disease. World J Gastrointest Pharmacol Ther. 2014;5(3):105-112. doi:10.4292/wjgpt.v5.i3.105
Drake C, Roehrs T, Shambroom J, Roth T. Caffeine Effects on Sleep Taken 0, 3, or 6 Hours before Going to Bed. J Clin Sleep Med JCSM Off Publ Am Acad Sleep Med. 2013;9:1195-1200. doi:10.5664/jcsm.3170

This article contains general information about medical conditions and potential treatments. It is not medical advice. If you have any medical questions, please consult your doctor.

1036935/1 08/2026