A metered-dose inhaler delivers a dose to a cat only when the drug reaches the lower airway, and a bare mouthpiece wastes most of it in the mouth. The spacer and mask are what turn 1 puff into something the lungs can use. Three numbers decide success: 1 puff per session, a 10 second wait for the chamber to fill, and 10 to 15 breaths taken through a sealed mask.
Most cats accept the routine in 2 to 4 weeks if the first 7 days involve no drug at all.
Three parts, one number that matters
The kit is a canister, a valved holding chamber, and a soft rubber mask. Canisters in feline use are usually 100 micrograms of salbutamol or 110 to 250 micrograms of fluticasone, with 200 actuations per canister. The chamber is the part people buy wrong. A 200 ml chamber holds one puff long enough for a cat taking fast, shallow breaths; a 50 ml pediatric chamber is empty before the cat has taken 4 breaths.
Masks come in 3 sizes and the fit rule is simple: the mask should cover the muzzle from 1 cm behind the whisker pads to the chin, with the nose inside the cone, not pressed into the plastic. A 3.5 kg cat usually takes the small mask, 3.5 to 5.5 kg the medium, and above 5.5 kg the large.
Prime, shake, wait 10 seconds
A new canister needs 4 priming puffs into the air. A canister unused for 2 weeks or more needs 1. Shake for 5 seconds before every session, because the drug settles out of the propellant within hours of standing.
Then the step almost everyone skips: fire 1 puff into the chamber and wait 10 seconds. The mist needs that long to slow down and fill the chamber instead of bouncing off the back wall. A cat that inhales at second 1 gets propellant in the face and very little drug. Two puffs into one chamber: the second displaces the first cloud, and the cat still breathes the same 10 to 15 breaths.
The 3 second mask test
Do not start with a chamber full of mist. Work up in 4 steps over 7 to 10 days, 2 short sessions a day:
Step 1, mask resting on the counter while the cat eats 2 treats beside it. Step 2, mask touched to the muzzle for 1 second, treat immediately. Step 3, mask held on for 3 seconds with a hand, no strap. Step 4, mask attached to the empty chamber for 3 to 5 seconds.
The gate is 3 seconds with no head pull, no ear flattening, and no paw push. A cat that holds that for 3 days in a row is ready for a real puff. A cat that pulls back twice in one session goes back one step for 2 days rather than forward.
Count the breaths, not the clock
Attach the mask, keep the chamber vertical, and count the valve flutter. At 20 to 30 breaths per minute, 10 to 15 breaths takes 20 to 40 seconds. Stop at 15 breaths or at 45 seconds, whichever comes first.
Six breaths is the working minimum. Under 6, repeat once with a fresh puff, and never give more than 2 puffs in a session. Holding the cat for 60 seconds to chase a perfect count costs more than 3 missing breaths; the struggle is what the cat remembers tomorrow.
Wipe the face, every time
Steroid settles on the muzzle and gets groomed off. Wipe 2 passes with a warm damp cloth across a 5 cm band from the nose bridge to the chin, then 1 dry pass, moving away from the eyes. Do it within 1 minute of removing the mask, before the cat licks.
This is also where you check the seal. A ring of condensation on the fur means the mask leaked at that edge; a dry patch around one nostril means the nose was pressed to the plastic and the cat was breathing around it.
When rinsing the mouth is not possible
Cats cannot rinse and will not spit. Swallowed fluticasone has an oral bioavailability under 1 percent, which is why it is the usual choice over beclomethasone for long-term feline use: what lands in the mouth and gets swallowed is mostly inactivated in the gut and liver. That does not make residue free.
The replacement routine is 3 steps. Offer 5 to 10 ml of water from a syringe into the cheek pouch, or 1 teaspoon of wet food, within 2 minutes of the puff. Wipe the muzzle as above. Then keep the cat from grooming the mask area for 5 minutes by offering a toy or a second teaspoon of food. A chamber with a one-way valve plus a mask that covers the nose does most of the work by keeping the plume out of the mouth in the first place.
Clean weekly, replace on a schedule
Wash the chamber once a week in warm water with 1 drop of plain dish soap, soak 5 minutes, rinse, and air dry for 24 hours without a towel, since rubbing builds static that holds the drug to the walls. Replace the chamber every 6 to 12 months or after 3 drops onto a hard floor, whichever comes first.
At 2 puffs a day, a 200 actuation canister lasts 100 days, but the last 20 doses run weak. Write the start date on the canister and replace at day 80, not when it feels empty.
Table: the numbers for one session
| Step | Target | Time | What goes wrong |
|---|---|---|---|
| Prime new canister | 4 puffs | 10 s | First 2 doses 30 to 50% weak |
| Shake | 5 s | 5 s | Drug settled, dose varies |
| Load chamber | 1 puff | 1 s | 2 puffs displace each other |
| Settle | 10 s wait | 10 s | Propellant hits the face |
| Mask seal | 3 s hold | 3-5 s | Leak over 2 mm at one edge |
| Breaths | 10-15 | 20-40 s | Under 6, repeat once |
| Face wipe | 2 wet, 1 dry | 15 s | Steroid left on the fur |
| Chamber wash | 1 per week | 5 min soak, 24 h dry | Static and film build up |
When to stop and call the vet
Judge the routine at 30 days, not at 3. A cat still fighting the mask at day 30 needs a different mask size or a 2 person technique, not more force. Call the clinic if resting breathing stays above 30 breaths per minute, if the abdomen works visibly on every breath, if the cat breathes with the mouth open at rest, or if rescue puffs are needed more than 2 times in 24 hours.
Refills and rechecks follow one calendar: the asthma inhaler protocol covers the drug side, and the vaccine calendar tool keeps both schedules in one place. Cats that hide after a session usually have a litter box problem on top of it, covered in digging after use.
Four things to do tomorrow: 7 days of mask-only sessions, 1 puff and a 10 second wait, 10 to 15 counted breaths, then a wipe and a teaspoon of wet food.
Frequently asked
How do I know the cat actually inhaled the dose?
Watch the valve on the chamber: each breath makes it flutter, and you should count 10 to 15 flutters in 20 to 40 seconds. If the valve sits still for 3 sessions in a row, the mask is leaking at one edge or the nose is pressed into the plastic. A ring of condensation on the fur after removal marks exactly where the leak is, so check the muzzle before you wipe it.
Can I give 2 puffs into the spacer at once to save time?
No. A single puff already fills a 200 ml chamber with the volume one cat can breathe in 10 to 15 breaths, and a second puff displaces that cloud, so the cat still takes 10 to 15 breaths but the dose is unpredictable. Wait 30 seconds between puffs, reload the chamber once, and count the breaths again, with a maximum of 2 puffs per session.
What if the cat holds its breath or panics with the mask on?
Drop back one step for 2 days and use the empty chamber again. Three seconds of contact with a treat is the gate, and a cat that holds its breath is usually one that was held too long once. If panic continues past 30 days, ask for a smaller mask, a 2 person technique, or a different device rather than forcing the current one.