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Inhalation AUGUST 2015 15 relief. These days, however, the anticholinergic is likely to be long acting in nature (LAMA), and augmented with a LABA. The use of ICS is controversial in the treat- ment of COPD where an asthmatic (reversible bron- choconstrictive) component is not present. 16 However, there is a school of thought that many patients present- ing with COPD symptoms also have an asthmatic com- ponent to their condition, so that therapy by ICS/LABA may be prescribed in a precautionary way to address both conditions simultaneously. 12 Recently, triple com- bination therapy in a single inhaler has become possible with ICS/LAMA/LABA medications for these patients. Combination therapies have the advantage pertinent to the older patient, that only a single inhaler device is needed to manage the disease(s) under treatment. 17 Devices The main classes of devices for oral inhalation are: a) the pressurized metered dose inhaler (pMDI), with or without valved holding chamber (VHC) add-on device to mitigate medication loss associated with imperfect patient coordination of inhalation with pMDI actua- tion; b) the dry powder inhaler (DPI), which may contain the powdered formulation in either a reservoir or as a single dose (capsule or pre-packaged blister-based) arrange- ment; c) the soft mist inhaler (SMI), of which the Respimat ® device (Boehringer Ingelheim, Germany) is the sole rep- resentative; d) the liquid droplet nebulizer, where the drug product(s) is either dissolved in aqueous solution or pre- pared as an aqueous suspension. Pneumatically-operated nebulizers are still widely used either in the hospital environment where compressed air at high pressure (50 psig) is the norm, or in the home environment where lower pressure table-top or portable air compressors are available. The simplest devices deliver the medication continuously at a fixed rate. More advanced pneumatic nebulizers make use of the addi- tional air flow generated during the inhalation portion of each breathing cycle (air entrainment) to augment the delivery rate of medication. The most advanced devices in this category contain a storage device to retain the aerosolized medication during exhalation, or are purely breath-actuated, delivering medication only when the patient inhales. Breath-actuated nebulizers (BANs) con- serve medication if the patient removes the mouthpiece temporarily, possibly to converse with a neighbor or caregiver. They also limit contamination of the local environment with the aerosolized medication droplets. More recently, electronic nebulizers, beginning with ultrasonic, followed by vibrating mesh/membrane designs, have become popular because they are efficient and have less medication wastage, therefore offering the potential for shorter treatment times. 18 However, they are more expensive, since they contain electronic as well as mechanical components. Inhaler suitability for the older patient The wide array of inhaler choices provides an opportu- Figure 1 Therapies associated with asthma, COPD and asthma combined with COPD Use primarily in asthma Short acting SABA class: e.g. salbutamol sulfate: 4 x daily dosing Long acting LABA class: e.g. formoterol fumarate: 2 x daily dosing Ultra-long acting ULABA class: e.g. indicaterol maleate: 1 x daily dosing Short acting SAMA class: e.g. ipratropium bromide: 3 x to 4 x daily dosing Long acting LAMA class: e.g. tiotropium bromide: 1 x daily dosing 'Soft' steroid with limited systemic effects: e.g. mometasone furoate: 1 x or 2 x daily Anti-Cholinergic Agonists Beta-2 Adrenergic Agonists Inhaled Corcorticosteroids (ICS) Combination products Conventional steroid with potential for systematic side effects: e.g. beclometasone di-propionate: 2 x daily Use primarily in COPD Use in asthma and in COPD Use primarily in asthma Less frequently in COPD e.g. tiotropium bromide/ formoterol fumarate e.g. ipratropium bromide/ salbutamol sulfate e.g. fluticasone propionate/ salmeterol xinafoate e.g. umeclidinium bromide/ vilanterol/ fluticasone fumarate LABA/ICS SAMA/SABA LAMA/LABA LAMA/LABA/ICS