Mechanisms and solutions for nasal drug delivery - a narrative review

The aim of this paper is to review mechanisms and solutions for nasal drug delivery. Literature survey was performed via PubMed, Google Scholar, Google, and ProQuest Central database of Kirikkale University. The nasal lining presents a large area of endothelium of variable permeability and with a rich vascular supply. Advantages of this route include eliminating first-pass metabolism and being easily accessible. The nasal route enables some agents which are otherwise difficult to administer to enter the systemic circulation, for example, low molecular mass compounds with high polarity, peptides, or proteins. There are three principal factors that influence the extent to which drugs can be absorbed through the nasal lining, namely the physico-chemical characteristics of the drug molecule itself, the action of the mucociliary system within the nose, and the presence of any factors increasing nasal absorption. A key factor limiting the use of the intranasal route of administration is insufficient absorption through the nasal mucosa. A number of drugs in development cannot be administered intranasally because their bioavailability following nasal administration is too low. There has been considerable research focus on methods to enhance absorption via the nasal mucosa. In this chapter, we review the literature related to this problem and discuss potential solutions.

Ciliary function and sinonasal mucosal cytology in pediatric patients with chronic rhinosinusitis during a year after functional endoscopic sinus surgery

BACKGROUND

The objective of the study is evaluation of ciliary function and mucosal cytology after endoscopic sinus surgery in children with chronic rhinosinusitis (CRS).

METHODOLOGY

A total of 132 children with CRS who underwent endoscopic sinus surgery, as well as 15 healthy controls were involved in the study. In this follow-up study patients were examined preoperatively, as well as 3, 6, 9, and 12 months after endoscopic sinus surgery. Assessment of ciliary function and sinonasal mucosal cytology was performed using high-speed videomicroscopy. Lund-Kennedy, Lund-Mackay, and sinonasal outcome test 20 (SNOT20) scores were also evaluated.

RESULTS

Total SNOT-20, Lund-Mackay, and Lund-Kennedy values significantly decreased after sinus surgery. In contrast, ciliary function and mucosal cytology only tended to improve after 6 months. 9 months after surgery the number of ciliated cells, ciliary beat frequency, cell viability, and ciliary length were significantly higher than preoperatively. The most significant improvement of ciliary function and cell height was observed 12 months after operation, whereas epithelial dystrophy and neutrophil infiltration were significantly reduced.

CONCLUSIONS

Substantial improvement was observed only in a year after surgery, whereas 0 to 3 months after the surgery ciliary function was severely impaired thus predisposing to recurrent sinusitis or other complications.

European Position Paper on Rhinosinusitis and Nasal Polyps 2020

The European Position Paper on Rhinosinusitis and Nasal Polyps 2020 is the update of similar evidence based position papers published in 2005 and 2007 and 2012. The core objective of the EPOS2020 guideline is to provide revised, up-to-date and clear evidence-based recommendations and integrated care pathways in ARS and CRS. EPOS2020 provides an update on the literature published and studies undertaken in the eight years since the EPOS2012 position paper was published and addresses areas not extensively covered in EPOS2012 such as paediatric CRS and sinus surgery. EPOS2020 also involves new stakeholders, including pharmacists and patients, and addresses new target users who have become more involved in the management and treatment of rhinosinusitis since the publication of the last EPOS document, including pharmacists, nurses, specialised care givers and indeed patients themselves, who employ increasing self-management of their condition using over the counter treatments. The document provides suggestions for future research in this area and offers updated guidance for definitions and outcome measurements in research in different settings. EPOS2020 contains chapters on definitions and classification where we have defined a large number of terms and indicated preferred terms. A new classification of CRS into primary and secondary CRS and further division into localized and diffuse disease, based on anatomic distribution is proposed. There are extensive chapters on epidemiology and predisposing factors, inflammatory mechanisms, (differential) diagnosis of facial pain, allergic rhinitis, genetics, cystic fibrosis, aspirin exacerbated respiratory disease, immunodeficiencies, allergic fungal rhinosinusitis and the relationship between upper and lower airways. The chapters on paediatric acute and chronic rhinosinusitis are totally rewritten. All available evidence for the management of acute rhinosinusitis and chronic rhinosinusitis with or without nasal polyps in adults and children is systematically reviewed and integrated care pathways based on the evidence are proposed. Despite considerable increases in the amount of quality publications in recent years, a large number of practical clinical questions remain. It was agreed that the best way to address these was to conduct a Delphi exercise . The results have been integrated into the respective sections. Last but not least, advice for patients and pharmacists and a new list of research needs are included. The full document can be downloaded for free on the website of this journal: http://www.rhinologyjournal.com.