In general, Primatene Mist appears safe if used appropriately. An article in Chest , the journal of the American College of Chest Physicians, concluded that "the occasional use of OTC epinephrine inhalers appears to be safe and effective when used according to labeled instruction by individuals with only mild, intermittent disease." However, the authors went on to point out that 20% of people using OTC epinephrine inhalers like Primatene Mist should not be using them, and should actually be on other asthma medication and under the care of a physician.
Studies with oral and intravenous dosing of radiolabeled ciclesonide have shown an incomplete extent of oral absorption (%). The oral bioavailability of both ciclesonide and the active metabolite is negligible (<% for ciclesonide, <1% for the metabolite). Based on a γ-scintigraphy experiment, lung deposition in healthy subjects is 52%. In line with this figure, the systemic bioavailability for the active metabolite is >50% by using the ciclesonide metered dose inhaler. As the oral bioavailability for the active metabolite is <1%, the swallowed portion of the inhaled ciclesonide does not contribute to systemic absorption.
This confusing situation happens often, even when the
rescue and maintenance inhalers are of
different color. The root problem is lack of standardization
among inhalers, with unclear labeling to distinguish between
rescue and maintenance inhalers. A contributing cause is
lack of proper education for both the caregivers and their patients .
All too often proper instructions were not given
when the drug was first prescribed. And even when they are provided,
patients sometimes don't really understand, or they forget.
Either way, having similar inhalers for different purposes
is an invitation to error. (This was less likely to be a problem
when the drug was studied
by the drug companies; see YELLOW BOX above, under 'DPI Type 2'.)
The problem is compounded when patients are on multiple
inhalers, eg, Proventil for rescue, Advair and Spiriva for
maintenance. That's 3 separate devices with two different
purposes -- easy for the patient to get confused. (Pills and
capsules come in many colors and sizes, but they are all
swallowed the same way.) What's needed is a universal delivery
device for all inhalers, with perhaps just two colors:
red for rescue drugs and green for maintenance drugs.
Anyone with clinical interest in the inhaler problems discussed above
(Errors 1 & 2) should definitely read
Problems With Inhaler Use: A Call for Improved Clinician and Patient Education ,
by James B. Fink and Bruck K. Rubin (Respiratory Care, Sept 2005, Vol 50, No. 10,
3. Not checking some objective measurement of the patient's air flow obstruction.
Every patient should have a breathing test to ascertain the degree of
impairment caused by the asthma. The most frequently performed
test is 'spirometry', which takes just a few minutes and requires the
patient to exhale forcefully thru a testing device (shown below).
A patient performing the spirometry test
Graphs from a normal spirometry test; left panel, graph of flow vs. volume; right panel, graph of time vs. volume.