Getting started with CPAP: a guide to the first weeks

Q: I can't fall asleep with the mask. What should I do?

It is the most common problem at the start. Put the mask on 20 to 30 minutes before you turn off the light, with the machine running and the ramp on, while you read or watch TV. Your brain needs to learn to link the mask with sleep rather than with being awake. If you stick with it, most patients end up falling asleep normally with their mask.

Q: My mouth is dry in the morning. Is that normal?

It is common at the start of treatment. It means you are partly breathing through your mouth, which lets the pressurized air escape. Solutions: turn up the heated humidifier, try a chin strap to keep your mouth closed, or switch to a full face mask that covers the nose and mouth. Do not wait for it to pass: it is one of the common reasons people give up on CPAP.

Q: I wake up several times a night with the mask. Is that normal?

In the first weeks, yes. Your brain is not yet used to sleeping with a steady airflow, and these awakenings usually become less frequent over time. If you take the mask off, put it back on as soon as you notice: even 3 to 4 hours a night is a good start. If the awakenings continue beyond a month, talk to your CPAP provider.

Q: My residual AHI is still 8. Is that serious?

A residual AHI between 5 and 10 is worth looking into, but it is not an emergency. Below 5, treatment is considered effective. Between 5 and 10, common causes are mask leaks, a pressure that is slightly too low, or sleeping on your back. Contact your CPAP provider: an adjustment is often enough. If it stays above 10 despite good use, a reassessment at the sleep center is needed.

Q: Can I take a break from treatment for a few days?

A few days without CPAP is generally not dangerous in the short term, but talk to your doctor if you drive a lot or have other health problems. In practice, breaks undo some of the progress you made getting used to it, and the first nights back are often hard. Under the NIHDI convention, a night without use counts as zero hours in the average. If something specific comes up (travel, a hospital stay), talk to your CPAP provider.

Q: How do I know if my pressure is right?

Two indicators in your CPAP data: residual AHI (ideally below 5, and best of all below 2) and leaks (below 24 L/min at the 95th percentile, the ResMed threshold). If you still wake up tired, have morning headaches, or your AHI stays high despite good use, the pressure may need reassessing. Never change the settings yourself: contact your CPAP provider or your sleep doctor.

1 The first night

A bedroom in the evening, with a CPAP machine on the bedside table, a nasal mask, the tubing and the machine screen, ready for the first night of treatment

The first night is rarely a complete success, and that is perfectly normal. Your body and brain are discovering something entirely new: a steady flow of air on your face, the quiet hum of the machine (25 to 30 dB, quieter than a fridge), the feel of the mask.

My most useful tip: put the mask on 30 minutes before you turn off the light, with the machine running. Watch TV, read, do something you enjoy. The goal is not to sleep: it is to get used to the feeling, without the pressure of "I have to fall asleep now."

Noise

25-30 dB

Quieter than a fridge. If it whistles, it is the mask, not the machine.

Night 1 goal

Try

No minimum time. One hour is already a start.

If you take the mask off

Put it back

Taking it off is not a failure. Putting it back on is a success.

Breathing through the mouth is common on the first night: if you wake up with a dry mouth, see the humidifier and chin strap below. Above all, do not draw conclusions from a single bad night.

2 The first weeks: what to expect

Getting used to CPAP often follows the same path. At first it is uncomfortable, and that is normal: your body and brain are learning to sleep with something new on your face. Here is what you can reasonably expect.

Adapting to CPAP over 4 weeks: perceived difficulty goes down and hours of use per night go up, from week 1 (difficult) to week 4 (habits)

Week 1: adjusting

It is hard, and that is normal

Leaks, discomfort, trouble falling asleep with the mask. Waking up often. A feeling of fighting the machine when you breathe out. Perhaps a dry mouth in the morning. All of this is expected.

Goal for the week

Wear the mask 2 to 3 hours a night on average. No more: just get used to it gradually.

Weeks 2-3: progress

Fine-tuning

You sleep longer with the mask. Start fine-tuning: strap tension (one finger should slide underneath), tubing position, humidifier level. If the dry mouth persists, now is the time to turn up the humidifier or try a chin strap.

Goal for this period

Get past 4 hours a night. Find and fix whatever still bothers you.

Week 4: first review

Reading the data

This is a good time to look at your CPAP report for the first time. Check your residual AHI: ideally below 5, and best of all below 2. If it regularly stays above 5, contact your CPAP provider: the pressure or the mask probably needs adjusting. Do not let it drag on.

Key action

Open your CPAP report and check: residual AHI, leaks (L/min), hours of use.

Months 2-3: comfort sets in

You have made it

You no longer think about putting the mask on: it has become automatic, like brushing your teeth. Daytime alertness often improves: less sleepiness in the afternoon, better focus, a better mood. That is why it is worth sticking with it.

If you are not at this point after 2 months of good use, talk to your sleep doctor: the pressure may need reassessing, or another problem may need looking into.

3 The settings that matter

Heated humidifier

Very helpful, especially in winter when the air is dry. Start around the middle of your machine's setting range, then adjust to how you feel. Too low: dry mouth, blocked nose. Too high: condensation in the tubing, with water gurgling right into the mask. If you have heated tubing (ClimateLine on ResMed machines, for example), use it: it greatly reduces condensation.

Ramp

The ramp starts the machine at a low pressure, then raises it gradually to your treatment pressure over an adjustable time. It makes falling asleep much easier: you do not get the full airflow in your face as soon as you close your eyes. If it is not turned on, look for it in the machine's comfort menu or ask your CPAP provider.

Pressure: do not change it without medical advice

Your pressure is set by your sleep doctor. It is tempting to adjust it yourself, but a pressure that is too high causes leaks, swallowed air and awakenings, while a pressure that is too low does not treat your apneas. If you think it is not right, ask your CPAP provider or your doctor to reassess it: that is their job.

Fixed CPAP or auto-CPAP: what is the difference?

Fixed CPAP

Delivers the same pressure all night. Simple and effective when the pressure has been properly determined. Does not adapt to changes in position or sleep stage.

Auto-CPAP (APAP)

Adjusts the pressure continuously, within a range set by the doctor. The average pressure is often lower, which many patients find easier to tolerate. Your doctor decides between the two.

4 Choosing and fitting your mask

At the start of treatment, the mask is often the heart of the problem, and so of the solution. A mask that does not suit your face or the way you sleep will be uncomfortable, however good the machine. The good news: there are dozens of models, and your CPAP provider is there to help you find the right one.

Golden rules for fitting

→ Snug, not airtight. Slide a finger under the strap: if you cannot, it is too tight. Tightening further to stop a leak often makes it worse.
→ Fit it lying down, not standing up. Your face changes shape when you lie down. Adjust the straps in your usual sleeping position, with the machine running.
→ Still leaking? Try another type. Leaks that persist despite every adjustment often mean the mask type does not suit your face. There are three: nasal pillows, nasal, full face. Careful: never block the small holes in the mask. They are the intentional leak vents, and they are essential to your safety.
→ Replace the cushion regularly. The silicone cushion wears out and stops sealing well. Replace it as often as your mask manufacturer recommends.

To learn all about mask types and how to choose one for your face and sleeping position:

Full guide: choosing a CPAP mask

The NIHDI (INAMI/RIZIV) 4-hour rule

What you need to know to keep your coverage

In Belgium, the NIHDI CPAP convention ties the renewal of your coverage to one condition: at least 4 hours of use a night on average. The average is calculated over at least 2 months at the first renewal, then over at least 9 months for each renewal after that.

It is an average, not a minimum for every night: a 2-hour night can be made up for by a 6-hour night. But a night without CPAP counts as zero. Below 4 hours, a short 3-month approval, the "joker", gives you time to get back above the line.

In practice, if you aim for a full night with the mask, you are comfortably above the threshold, and your treatment works as well as it can.

Understand the whole CPAP convention →

Common questions from beginners

The real questions everyone asks, with honest answers.

I can't fall asleep with the mask. What should I do?

My mouth is dry in the morning. Is that normal?

I wake up several times a night with the mask. Is that normal?

My residual AHI is still 8. Is that serious?

Can I take a break from treatment for a few days?

How do I know if my pressure is right?

Going further

CPAP gets easier with time and the right tools. These guides will help you progress step by step.

Side effects: causes and solutions Choosing a CPAP mask Reading your CPAP report The NIHDI CPAP convention Sleep hygiene Traveling with CPAP

A problem with your CPAP?

Side effects and how to fix them

Dry mouth, leaks, noise, swallowed air... Problems are common at the start. The good news: there is a solution for each one.

See the solutions