Guide · dry eye
CPAP and dry eyes
Sore, gritty, red eyes every morning since the machine arrived: it’s the air. A little of it leaks up over the mask all night and dries the surface of the eye. Three things fix most of it, and one of them is having your glands checked.
Why it happens
Even a well-fitted CPAP mask leaks a little, and the leak goes upwards — across closed lids, and into any eye that doesn’t quite close in sleep. Eight hours of moving air, every night. Add a bedroom that’s dry and warm and you wake with eyes that feel like sand.
Tonight
The mask fit. Most leaks are at the bridge of the nose; a refit, a different size or a nasal-pillow mask often ends it. Your sleep clinic or supplier will do this. The humidifier, turned up. A drop of gel at bedtime — thicker than a drop, lasts the night.
The part that’s yours
If the oil glands in your eyelids are already blocked — they are in most people who’ve had dry eye for a while — the leak turns a mild problem into a bad one, because there’s no oil layer to slow the evaporation. The £15 gland scan shows whether they are; clearing them makes the eye far more resistant to the air. Plenty of CPAP patients find that after treatment the leak stops mattering.
Don’t stop the machine
Sleep apnoea untreated is worse for your eyes (and your heart) than the dryness. Fix the eyes, keep the CPAP.
The three types of dry eye, and what we do for each
Most people are told “you’ve got dry eyes” and handed drops. But there are three different causes, and each needs something different. Most people have a mix.
Blocked oil glands: meibomian gland dysfunction (MGD)
In one large study, 86% of people with dry eye had signs of this. Along the edge of your eyelids are tiny glands, about 30 in the top lid and 25 in the bottom, that put a thin layer of oil on your tears. When they block, your tears dry up in seconds, however much water your eyes make. It feels gritty, burning and tired, often worse on screens or by evening. Drops help for an hour, because they don’t unblock the glands.
What we do: photograph your glands so you can see them, warm and clear them in clinic, clean the lid edge, and use IPL or light therapy where it helps. Then we give you a simple routine for home.
Not enough tears
Your eyes don’t make enough of the watery part of tears. This is more common with age, some medicines, the menopause, and conditions like Sjögren’s.
What we do: measure your tear level, choose the right drops for you, and use tiny plugs to keep your own tears in where they help. We’ll write to your GP if something needs checking.
Inflamed eyelids: blepharitis, often with tiny mites called Demodex
Crusty, itchy, red lid edges, often worse in the morning.
What we do: deep-clean the lid edge in clinic, treat the mites, and show you how to keep the lids clean at home.
Not sure which one you have? That’s what the assessment is for. We look at your glands, tears and lids, and tell you which type, or which mix.
The short version
- Mask leak dries the eye surface all night
- Refit the mask, turn up the humidifier, gel at bedtime
- Blocked oil glands make it far worse — the Dry Eye Assessment shows if they are
- Keep using the machine