Does Alcohol Change Your Overnight Oxygen?

You've had a couple of drinks and you wake up feeling rough. Was it the hangover, or did your night look different too? If you own an overnight oximeter, you can check.

What did the studies find?

Alcohol relaxes the muscles that help keep your upper airway open while you sleep.

• A small 1982 study found more snoring and more breathing events after evening alcohol in the men it tested.
• A 2018 review pooled 14 controlled studies. Alcohol before sleep was associated with more breathing events and a slightly lower average SpO2.

Those are averages across groups of people. They don't say what your own nights will look like.

How do you run the comparison?

You need three kinds of night:

• No alcohol. Your baseline.
• Early drink. Last drink at least three to four hours before bed.
• Late drink. Last drink close to bedtime.

Then:

1. Record a few nights of each kind over two to three weeks.
2. Write down the time of your last drink and roughly how much you had.
3. Keep bedtime, dinner time and sleeping position as steady as you can.

Don't drink more than you usually would for the sake of the experiment. Compare the nights you'd have anyway.

Which numbers should you compare?

• ODI, the number of dips per hour.
• Your lowest reading of the night.
• Minutes below 90%.
• Your overnight pulse. Alcohol often raises resting heart rate for the night, so this may differ even if your oxygen doesn't.

Also look at when the dips happen. On late-drink nights, check whether they cluster in the first half of the night. An oximeter doesn't record snoring, so use a snoring app alongside it if you want the sound too.

What if one night looks very different?

One night doesn't tell you much. Your numbers move around from night to night for reasons that have nothing to do with drinking. Here's how many nights to record before you compare.

Does a clean result mean you're fine?

No. An oximeter is not a sleep study, and it can't tell you whether you have a sleep condition. If you snore loudly, someone has heard you stop breathing or gasp, or you're exhausted during the day, see a doctor whatever your numbers say. And if you take any medication, ask your doctor or pharmacist how it combines with alcohol.

How do you keep track of it all?

The device's own app shows one night at a time, so you'd be comparing from memory. In PulseOxTracker you can tag each night as "no alcohol", "early drink" or "late drink" and see the average ODI for tagged nights next to the rest.

Not a medical device. Does not diagnose, treat or prevent any condition. Discuss results and changes with a clinician.

References

1. Issa FG, Sullivan CE. Alcohol, snoring and sleep apnea. Journal of Neurology, Neurosurgery and Psychiatry. 1982;45:353-359. doi:10.1136/jnnp.45.4.353
2. 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 Medicine Reviews. 2018;42:59-67. doi:10.1016/j.smrv.2018.05.007