Closer to an 'Ideal Inhaler' With the Easyhaler
Closer to an 'Ideal Inhaler' With the Easyhaler
The characteristics of an ideal inhaler are based around the design and formulation of the device, patient use and the clinical effect, together with concordance and patient preference. To ensure consistent drug delivery to the lungs, with regular adherence to the prescribed dosage regimen, it is essential that all these characteristics simultaneously interact to provide smooth and sustained therapeutic control affected only by the clinical status of the patient. The literature highlights that dose emission from an Easyhaler is fairly consistent irrespective of the inhalation technique used by patients of all age groups. Clinical studies have shown equivalence of this device to those frequently prescribed and that it is preferred by many patients. Although further research is required into the development of inhalation devices, the literature describing the Easyhaler dry powder inhaler indicates how an inhaler can closely meet the criteria for an ideal inhaler.
The metered-dose inhaler (MDI) is the most commonly prescribed inhaler device as it is accepted by many patients and, in general, it consistently emits a constant dose. However, it is renowned for problems with inhalation technique as it requires patients to co-ordinate inhalation with delivery of the medication from the canister and the need to constantly counsel patients about their inhalation technique. In addition, some patients naturally stop inhaling partway through inhalation because of their response to the cold aerosol hitting the back of their mouths. This has been improved by breath actuation, but can still prove to be a problem in many patients.
As a result of a ban on chlorofluorocarbons (CFCs), pharmaceutical companies switched more of their development resources to dry powder inhalers (DPIs) as an alternative to the MDI, starting with the multidose Turbuhaler (AstraZeneca, Lund, Sweden) in 1988. In addition, since the release of medication in all DPIs is by breath actuation, DPIs overcame the patient use problem of coordination when inhaling. The realization that lung deposition when using the Turbuhaler was twice that of a MDI fuelled research by other pharmaceutical companies to develop their own DPIs, with reports that focused on comparisons with the Turbuhaler. The challenge has been to introduce a multidose DPI according to the criteria described in figure 1. These are generally accepted as the qualities that designers aim to incorporate to create an ideal inhaler. The inhaled product includes the properties of the formulation with respect to the aerodynamic characteristics of the emitted dose and how these are affected by patient use and storage. The inhalation manoeuvre covers the range of inhalation techniques that patients will use together with their competence in achieving the inhalation technique recommended by the manufacturer of the product. The latter is important for DPIs because if the patient does not have sufficient inspiratory effort to inhale a respirable dose from the inhaler, then they will receive no dose. Safety includes local (oropharyngeal) effects and those associated with systemic delivery of the drug, whilst concordance involves patient acceptability and compliance. These criteria, described in figure 1, all combine during patient use.
(Enlarge Image)
Criteria for the ideal inhaler.
The Easyhaler (Orion Pharma, Espoo, Finland) [figure 2] has recently been launched in the UK [by Ranbaxy (UK) Ltd] and is more comparable to MDIs with respect to appearance and cost than other DPIs. Although the Easyhaler has been available in other European countries for 10 years, the benefits it provides continue to be important in comparison with other currently available DPIs. However, in order to fully assess the overall concept of the Easyhaler, it must be analyzed against each of the qualities associated with the ideal inhaler. This review intends to examine each of these criteria with respect to the Easyhaler and other inhalers.
(Enlarge Image)
The Easyhaler®.
The data for this review was sourced via PubMed, EMBASE and Web of Knowledge searches of English language papers, emphasizing the past 5 years of published work. Key words included: Easyhaler, Turbuhaler, dry powder inhaler, patient satisfaction with inhaler, patient preference of inhaler.
The characteristics of an ideal inhaler are based around the design and formulation of the device, patient use and the clinical effect, together with concordance and patient preference. To ensure consistent drug delivery to the lungs, with regular adherence to the prescribed dosage regimen, it is essential that all these characteristics simultaneously interact to provide smooth and sustained therapeutic control affected only by the clinical status of the patient. The literature highlights that dose emission from an Easyhaler is fairly consistent irrespective of the inhalation technique used by patients of all age groups. Clinical studies have shown equivalence of this device to those frequently prescribed and that it is preferred by many patients. Although further research is required into the development of inhalation devices, the literature describing the Easyhaler dry powder inhaler indicates how an inhaler can closely meet the criteria for an ideal inhaler.
The metered-dose inhaler (MDI) is the most commonly prescribed inhaler device as it is accepted by many patients and, in general, it consistently emits a constant dose. However, it is renowned for problems with inhalation technique as it requires patients to co-ordinate inhalation with delivery of the medication from the canister and the need to constantly counsel patients about their inhalation technique. In addition, some patients naturally stop inhaling partway through inhalation because of their response to the cold aerosol hitting the back of their mouths. This has been improved by breath actuation, but can still prove to be a problem in many patients.
As a result of a ban on chlorofluorocarbons (CFCs), pharmaceutical companies switched more of their development resources to dry powder inhalers (DPIs) as an alternative to the MDI, starting with the multidose Turbuhaler (AstraZeneca, Lund, Sweden) in 1988. In addition, since the release of medication in all DPIs is by breath actuation, DPIs overcame the patient use problem of coordination when inhaling. The realization that lung deposition when using the Turbuhaler was twice that of a MDI fuelled research by other pharmaceutical companies to develop their own DPIs, with reports that focused on comparisons with the Turbuhaler. The challenge has been to introduce a multidose DPI according to the criteria described in figure 1. These are generally accepted as the qualities that designers aim to incorporate to create an ideal inhaler. The inhaled product includes the properties of the formulation with respect to the aerodynamic characteristics of the emitted dose and how these are affected by patient use and storage. The inhalation manoeuvre covers the range of inhalation techniques that patients will use together with their competence in achieving the inhalation technique recommended by the manufacturer of the product. The latter is important for DPIs because if the patient does not have sufficient inspiratory effort to inhale a respirable dose from the inhaler, then they will receive no dose. Safety includes local (oropharyngeal) effects and those associated with systemic delivery of the drug, whilst concordance involves patient acceptability and compliance. These criteria, described in figure 1, all combine during patient use.
(Enlarge Image)
Criteria for the ideal inhaler.
The Easyhaler (Orion Pharma, Espoo, Finland) [figure 2] has recently been launched in the UK [by Ranbaxy (UK) Ltd] and is more comparable to MDIs with respect to appearance and cost than other DPIs. Although the Easyhaler has been available in other European countries for 10 years, the benefits it provides continue to be important in comparison with other currently available DPIs. However, in order to fully assess the overall concept of the Easyhaler, it must be analyzed against each of the qualities associated with the ideal inhaler. This review intends to examine each of these criteria with respect to the Easyhaler and other inhalers.
(Enlarge Image)
The Easyhaler®.
The data for this review was sourced via PubMed, EMBASE and Web of Knowledge searches of English language papers, emphasizing the past 5 years of published work. Key words included: Easyhaler, Turbuhaler, dry powder inhaler, patient satisfaction with inhaler, patient preference of inhaler.
