Applied Evidence

Inhalation therapy: Help patients avoid these mistakes

Author and Disclosure Information

Faulty technique can sabotage the best of treatment plans for asthma and COPD. Here are some common errors and how you can help patients avoid them.




Stress the importance of exhaling gently for a few seconds before inhaling (deeply and slowly for a metered dose inhaler, and deeply and rapidly for most dry powder inhalers). C

Observe the inhaler technique of every patient receiving inhalation therapy on more than one occasion. C

Don’t rely on self-reports regarding inhaler technique; despite claims of proficiency, most patients make at least one mistake. C

Strength of recommendation (SOR)

A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series

For patients with asthma or chronic obstructive pulmonary disease (COPD), inhalation therapy is the foundation of treatment. Yet all too often, patients don’t get the full value of their inhaled medications because they use their inhaler incorrectly. When technique is markedly flawed, suboptimal outcomes typically result.

Given the number of Americans with asthma (at least 22 million)1 and COPD (more than 13 million adults),2 faulty inhaler technique is a major public health problem. In fact, the number of people suffering from COPD may be even larger: Close to 24 million US adults are believed to have impaired lung function.3,4 For patients with asthma or COPD—many of whom are treated by family physicians—comprehensive education with a focus on correct use of an inhaler is essential.

In this review, we present evidence of frequent inhaler errors (from clinical studies) and highlight some of the more common mistakes (based on our clinical experience [TABLE]5). Finally, we offer ‘‘time-efficient’’ solutions to inhaler problems—steps that physicians in busy primary care practices can take to ensure that patients with asthma or COPD get the maximum benefit from inhalation therapy.

Caution patients about these device-specific mistakes*

Metered dose inhaler
  • Failing to shake inhaler well
  • Failing to exhale gently before inhaling
  • Exhibiting poor coordination (failing to press down on the canister and inhale simultaneously)
  • Inhaling rapidly (inhalation should be very slow)
  • Failing to inhale deeply or not inhaling at all
  • Failing to hold one’s breath long enough (10 seconds is optimal) or at all
  • Failing to wait long enough (≥30 sec) before the next puff
  • Pressing down on the canister 2 or 3 times in a row (this should be done only once)
  • Failing to inspect the mouthpiece for foreign objects, such as coins
  • Forgetting to periodically clean the actuator
  • Holding the device upside down (the mouthpiece should be on the bottom)
  • Leaving the cap on while pressing down
Metered dose inhaler plus spacer/VHC
  • Placing the inhaler in the wrong end of the VHC
  • Failing to shake the inhaler well
  • Failing to exhale slowly before inhaling
  • Waiting too long (several seconds) after pressing down on the device before inhaling
  • Pressing down on the canister 2 or 3 times in rapid succession (this should be done only once)
  • Inhaling rapidly (some VHCs whistle to alert the patient to reduce the rate of inhalation)
  • Exhaling instead of inhaling after pressing down on the canister
  • Failing to hold one’s breath long enough after a slow, deep inhalation (10 seconds is optimal)
Dry powder inhaler
  • Shaking the DPI (it’s not required with this type of device)
  • Forgetting to exhale gently before inhaling
  • Exhaling into the device (exhalation should be away from the DPI so the breath doesn’t clump the powder)
  • Inhaling slowly (with most DPIs, inhalation should be rapid)
  • Failing to inhale at sufficient inspiratory flow rate
  • Failing to load the dose
*These are examples based on the experience of the authors; other errors are possible.
Timing is not as crucial as it is for an MDI without a spacer, but the drug is still lost if inhalation is delayed.
Correct use varies by type of product (see product literature for specifics).
DPI, dry powder inhaler; MDI, metered dose inhaler; VHC, valved holding chamber.
Source: Adapted with permission from Self TH, et al. Consultant. 2003.5

Inhaler error is well documented

Since 1965, when it was first reported that many patients used metered dose inhalers (MDIs) incorrectly,6 evidence has accumulated supporting the magnitude of the problem.7-12 (Studies conducted in family practice settings are described in “Researchers look at inhaler problems in primary care” and in TABLE W1.13-20)

Researchers look at inhaler problems in primary care

A number of studies of various sizes (from 41 to 3955 patients) have assessed inhaler technique in patients being treated by clinicians in primary care. The researchers used a variety of scoring methods, as well. Among them were a simple 4-step (0-4) rating system, a 9-step system, a standardized inhaler-specific checklist, and a system that tracked the number of omissions patients made.13-20 All found significant problems with inhaler technique. (You’ll find a detailed look at the studies in TABLE W1 at

In one study of 422 patients,13 including young children, adolescents, and adults, participants received one point for correctly performing each of the following steps:

  • Adequate preparation (shaking well for those using a metered dose inhaler [MDI]; loading correctly for patients using a dry powder inhaler [DPI])
  • Adequate expiration, correct head position
  • Adequate inspiratory technique
  • Holding breath afterwards.

The researchers found that 25% of the patients had inadequate technique (≤2 on a 0-4 point scale). In this study, as in others that included patients using various types of devices, use of an MDI was associated with a higher rate of incorrect technique.

Another much-smaller study14 used the same 4-step system to assess the technique of 50 patients, all of whom had the same type of DPI and had received extensive training in the correct use of the device. Despite the training, 27% of the patients received scores of ≤2 (inadequate technique). Sixty-eight percent received a score of 3 (adequate); only 5% received a score of 4 (good).

The 2 largest studies—one including 3955 patients using MDIs20 and the other looking at 3811 patients using various kinds of devices18—found high levels of errors, as well. In the latter study, 76% of patients with MDIs made at least one error vs 49% to 55% of patients using DPIs.18 The results convinced a large majority of the physicians caring for these patients of the need to check inhaler technique more frequently. In the study of MDI users alone, 71% of the patients made at least one mistake.20 inhaler misuse was associated with higher asthma instability scores, this study showed.

More recently, a researcher assessed the effects of an integrated primary care model on the management of asthma and/or COPD in middle-aged and elderly patients, in a study of 260 patients in 44 family practices.19 The study included an evaluation of inhaler technique.

Participants were divided into an intervention group—137 patients who received education regarding inhaler use from a nurse—and a usual care group (123 patients). After 2 years, correct inhaler technique among those in the intervention group went from 41% at baseline to 54%. At the same time, the proportion of those in the usual care group with correct technique fell from 47% to 29%.19


Next Article: