Correct Technique for Using a Metered-Dose Inhaler (MDI)

Introduction to MDI Technique

The American Academy of Allergy, Asthma, and Immunology recommends that for patients ≥5 years old using a standard MDI, the optimal technique involves actuating the device during a slow, deep inhalation (30 L/min or 3-5 seconds) followed by a 10-second breath hold, and a spacer or valved holding chamber (VHC) must be used for patients who cannot coordinate actuation with inhalation 1, 2

The optimal technique for using a standard MDI involves positioning the MDI correctly, with the mouthpiece between the lips and teeth (closed-mouth technique), or using the open-mouth technique (holding MDI 2 inches away), which enhances lung delivery under laboratory conditions 1, 2
Patients should coordinate actuation with inhalation, beginning a slow, deep inhalation (30 L/min or 3-5 seconds) and actuating the canister at the start of inhalation 1, 2
Patients should continue inhaling slowly and deeply after actuation, and hold their breath for 10 seconds after completing inhalation 1, 2
After using inhaled corticosteroids, patients should rinse their mouth and spit to reduce systemic absorption and local side effects like thrush 1, 2, 3

A spacer or VHC is strongly recommended for all children <4 years old, as they cannot generate sufficient inspiratory flow or coordinate actuation 1, 4
A spacer or VHC is also recommended for patients who cannot coordinate actuation with inhalation, elderly patients with weak fingers, poor coordination, or cognitive impairment, and all patients using inhaled corticosteroids 1, 3, 4, 5

When using a spacer/VHC, patients should actuate only once into the spacer/VHC per inhalation, and begin slow, deep inhalation (30 L/min or 3-5 seconds) immediately after actuation 1, 4, 6
Patients should hold their breath for 10 seconds after completing inhalation 1, 4, 6

Plastic VHCs should be rinsed once monthly with low-concentration liquid household dishwashing detergent (1:5000 or drops per cup of water) and let drip dry to reduce static charge and enhance drug delivery 3, 4, 6

Patients should not stop inhaling at actuation, but rather continue inhaling slowly and deeply 1, 2
Patients should not inhale too rapidly, but rather at a slow rate (30 L/min) 1, 2
Patients should hold their breath for 10 seconds after inhalation to ensure proper drug delivery 1, 2

The American Academy of Family Physicians recommends shaking the inhaler before each use to ensure proper medication mixing, and priming the inhaler if it's new or hasn't been used recently, following manufacturer instructions 7
The American Academy of Family Physicians suggests waiting 10-15 seconds between puffs if multiple puffs are prescribed, with longer intervals offering no additional benefit 7
The American Academy of Allergy and Clinical Immunology recommends rinsing the mouth and spitting after using inhaled corticosteroids to reduce systemic absorption and prevent oral thrush, although this is not exclusively an American Academy of Allergy and Clinical Immunology guideline 8

The British Thoracic Society recommends using a spacer or valved holding chamber for elderly patients with weak fingers, poor coordination, or cognitive impairment 9, 10

The American Academy of Family Physicians recommends that physicians observe and regularly review patients' inhaler technique because many patients have difficulty with proper inhalation technique 7
The British Thoracic Society suggests that repetitive training improves technique, with patients trained 3 times having significantly higher rates of correct use, and the first treatment should be given under supervision 11, 12

The British Thoracic Society recommends considering an MDI with spacer and tight-fitting face mask, breath-activated inhaler, dry powder inhaler, or nebulizer as a last resort for patients who cannot master standard MDI technique despite proper instruction 9, 10