Mechanism of action of some commonly used nasal drugs

Rise and fall of decongestants in treating nasal congestion related diseases

INTRODUCTION

Decongestants are commonly used drugs in clinical practice, and it can relieve nasal congestion caused by factors like influenza, rhinitis and acute upper respiratory tract infection.

AREAS COVERED

In this article, we review the research outcomes about decongestants, which aim to provide beneficial information that can guide the clinical application of decongestants for clinician.

EXPERT OPINION

Although the use of nasal decongestants is increasingly limited, caution rather than prohibition is now advocated. Scientific and accurate use of nasal decongestants can achieve satisfactory clinical effectiveness on nasal congestion, and it is not easy to produce adverse reactions. Patients with severe nasal congestion may use nasal decongestants solely or in combination with nasal corticosteroids or nasal antihistamines to exert a synergistic effect. The concentration, dose, frequency and time of nasal decongestants determine whether drug-induced rhinitis will occur. Additionally, we recommend to patients not to buy nasal sprays with unknown ingredients on the internet or in pharmacy, so as to avoid the risk of rhinitis medicamentosa. For patients with rhinitis medicamentosa, the use of nasal decongestants should be stopped immediately. However, more evidence is still needed to standardize the clinical use of nasal decongestants.

Investigation of topical intranasal cocaine for sinonasal procedures: a randomized, phase III clinical trial

BACKGROUND

The objective of this trial was to demonstrate the clinical efficacy and safety of topical cocaine as part of the effort to gain regulatory approval from the United States Food and Drug Administration.

METHODS

This phase III, randomized, prospective, double-blind, multicenter, single-dose, placebo- and dose-controlled, parallel-group study aimed to evaluate the safety and efficacy of topical intranasal cocaine (RX0041-002). A total of 925 subjects were screened and a total of 648 subjects were randomized: 95 to placebo; 275 to 4% RX0041-002; and 278 to 8% RX0041-002. Efficacy was assessed with subjective pain intensity scores using the visual numeric rating scale and objectively using the von Frey filament test. Adverse events (AEs), vital signs, Holter monitoring, nasal irritation on visual examination, and smell assessment were recorded. The placebo and experimental groups were compared using a two-tailed Fisher's exact test.

RESULTS

Topical 4% and 8% cocaine achieved significant subject analgesia, the primary efficacy endpoint. Both doses were safe and well-tolerated, with a safety profile similar to placebo. In the 4% and 8% groups, headache (1.5% and 2.5%, respectively), epistaxis (0.7% and 1.1%), and anxiety (0.7% and 0%) were the only AEs reported by >1 subject. No cardiovascular AEs, serious AEs, or deaths occurred. A higher percentage of subjects in the 4% and 8% groups compared with the placebo group had a modest increase in either systolic or diastolic blood pressure.

CONCLUSION

Topical 4% and 8% cocaine is an effective anesthetic that can be safely administered for nasal procedures.

Systemic Pharmacokinetics of Topical Intranasal Cocaine in Healthy Subjects

Background

Topical cocaine is currently available for local anesthesia of the upper airway mucous membranes.

Objective

The objective of this study was to define the safety and efficacy of topical intranasal cocaine for a subsequent phase II clinical trial.

Methods

This study was a single-dose, single-center, and open-label study of the plasma and urinary pharmacokinetics (PK) of 4% topical cocaine and its major metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME), in 30 healthy subjects. Subjects received the topical solution on cotton pledgets containing 4 mL of 4% topical cocaine applied for 20 minutes, which was equivalent to 160 mg of cocaine hydrochloride.

Results

A total of 30 subjects (14 males and 16 females) were enrolled, treated, and provided PK data for analysis. Mean plasma concentrations of cocaine rose rapidly during the intranasal exposure period, with peak levels (Cmax, 37.0 ± 17.3 ng/mL) observed at the time of pledget removal (Tmax, 0.43 ± 0.34 h). Mean plasma concentrations then fell rapidly and monoexponentially for the remainder of the study, with a mean half-life (t1/2) of 1.04 ± 0.35 hours. Following a 20-minute topical intranasal exposure to a 160 mg dose of cocaine 4% solution, the mean 0 to 12 hours recoveries of cocaine, BE, and EME were 117 ± 67 μg, 816 ± 440 μg, and 275 ± 113 μg, respectively. Plotting urinary recovery by collection interval showed that urinary excretion of cocaine closely followed the time course of plasma cocaine.

Conclusions

Cocaine was rapidly but incompletely absorbed and then rapidly eliminated. Only 4% of the administered cocaine dose appeared to be absorbed in this study. Cocaine appeared in the urine with a time course similar to that in plasma.

Use of Mometasone Furoate Aqueous Nasal Spray in the Treatment of Rhinitis Medicamentosa: An Experimental Study

OBJECTIVE: We aimed to investigate, histopathologic changes in the nasal mucosa of guinea pig's after prolonged administration of oxymetazoline and the development of rhinitis medicamentosa, and the efficacy of mometasone furoate aqueous nasal spray and saline in reversing the ultrastructural changes attributable to rhinitis medicamentosa.

METHODS: In the study, 24 male guinea pigs (500 to 600 gr) were used. Oxymetazolin (0.05%) was sprayed into the nasal cavities of the guinea pigs 3 times daily for 8 weeks. At the end of this period, 6 guinea pigs were killed and examined to make sure that the animals had developed rhinitis medicamentosa. The remaining guinea pigs were randomly divided into 3 groups. In the first group, one spray-puff of 0.05% mometasone furoate aqueous nasal spray (50 μg) was applied twice daily for 14 days. In the second group, saline solution (0.9% NaCl) was applied twice daily for 14 days. No treatment was performed in the third group. At the end of the treatment period, nasal mucosal changes were evaluated by light microscopy and electron microscopy.

RESULTS: After oxymetazolin application for 8 weeks, the main histologic changes were edema, congestion, proliferation of subepithelial glands, and squamous cell metaplasia. After topical mometasone furoate aqueous spray application for 2 weeks, the edema fluid was found to diminish markedly. In the saline and no treatment groups, edema and congestion continued. In these groups of guinea pigs, fibrosis has been seen in the nasal mucosa.

CONCLUSION: We found that mometasone furoate nasal spray was effective against experimentally induced rhinitis medicamentosa in guinea pigs. Mometasone furoate nasal spray may have value in the treatment of patients with rhinitis medicamentosa.

Pathophysiology and progression of nasal septal perforation

OBJECTIVE

To review the prevalence, causes, and treatments of nasal septal perforation (NSP).

DATA SOURCES

A literature search was conducted in MEDLINE to identify peer-reviewed articles related to NSP using the keywords nasal septal perforation and septal perforation for articles published between January 1, 1969, and December 31, 2006, and references cited therein.

STUDY SELECTION

Articles were selected based on their direct applicability to the subject matter.

RESULTS

Causes of NSPs include piercings, exposure to industrial chemicals, illicit drug use, intranasal steroid use, surgical trauma, bilateral cautery, and possibly improper use of nasal applicators. Prevalence is poorly reported. Mechanisms of substance-induced NSP formation are not understood. Progression from epistaxis to ulceration to NSP could not be substantiated by the literature.

CONCLUSION

Depending on the patient, NSP may be viewed as desirable (nose rings), problematic (whistling, congestion), or inconsequential. Understanding the pathogenesis of NSP is important for the practicing physician required to make decisions about whether to recommend surgical correction or medical treatment. Although the etiology of NSP is overwhelmingly iatrogenic, there is an association with a number of medical diseases in addition to use of illicit drugs and/or prescription nasal sprays.

Efficacité de Dérinox® chez des patients souffrant d’une rhinite virale évaluée par un PNIF (Peak Nasal Inspiratory Flow)

OBJECTIVES

The aim of this study was to compare the efficacy and tolerance of Dérinox (D) to Rhinofluimucil (R) and placebo (P) in the treatment of common cold, using an objective measure of nasal obstruction, the Peak Nasal Inspiratory Flow (PNIF--Clement Clarke International, Harlow, Angleterre).

PATIENTS AND METHODS

This randomized, double-blind, double-dummy, parallel group study enrolled 354 patients (34 P, 165 D et 155 R) included by 85 general practitioners. The treatment duration was 5 days at usual recommended dosage regimens. PNIF measures were done before drug administration (T0) as well as 15 min and 3 h after each intake. Moreover, nasal obstruction, rhinorrhea and global discomfort were subjectively assessed.

RESULTS

The efficacy of D was superior to that of P and R when comparing PNIF from T0 to T3 h after the first intake. At T15 min, rhinorrhea was significantly improved with both active treatments and global discomfort was significantly improved with D only. Treatment tolerance was satisfactory and comparable between the 3 groups.

CONCLUSION

Efficacy of Dérinox(R) was superior to that of P and R for the improvement of the nasal obstruction (PNIF) between T0 and T3h (main criteria) after the first intake in patients suffering from common cold.

'Moffett's' solution: a review of the evidence and scientific basis for the topical preparation of the nose

General anaesthesia, often causes a widespread vasodilation, producing a hyperaemic nasal mucosa, hence the need for a topical application to decongest the nose and reduce the nasal blood flow to optimize the operative field. The use of a combination of cocaine, sodium bicarbonate and adrenaline given the eponymous title of 'Moffett's Solution' is standard practice in many rhinological procedures to provide local anaesthesia, vasoconstriction and decongestion. We discuss each component of 'Moffett's' reviewing the science and evidence behind its usage and the huge variation in the techniques of its application.

Topical active H1-antihistamines and their effect on nasal airway resistance

The introduction of a topically active H1-antihistamine nasal spray Azelastine, has given an extra dimension in the management of allergic rhinitis. The drug acts rapidly and avoids the systemic adverse effects of antihistimines. An objective prospective study was performed to detect the effect of Azelastine nasal spray on nasal airway resistance. Twelve healthy adult volunteers with no rhinological problems were included in the study. Nasal cavities were sprayed with 280 micrograms (two puffs) of Azelastine nasal spray and the nasal airway resistance was measured with anterior rhinomanometry at intervals of 30 minutes for up to two hours. Our study has shown a statistically significant increase in the total nasal airway resistance following the use of Azelastine nasal spray in the absence of a subjective change in nasal airway resistance. There are substances when inhaled which can cause subjective improvement in nasal airway patency without changing the measured nasal airway resistance. However this medication gives no subjective change in nasal airway patency in spite of increasing nasal airway resistance.

Allergic Rhinosinusitis: The Total Rhinologic Disease

Allergic rhinosinusitis has three forms of therapy: pharmacotherapy, immunotherapy, and surgical therapy. Pharmacotherapeutically, there are six classes of drugs that give symptomatic relief: mucolytics, decongestants, anticholinergic agents, antihistamines, mast cell stabilizers, and corticosteroids. All six classes are discussed individually and in detail.

For immunotherapeutic therapy of allergic rhinosinusitis, there are four types of skin testing in current use: scratch testing, prick testing, single intradermal testing, and skin end point titration testing. Only the latter is able to quantitate the antigenicity of each antigen, and thus the treatment vial made from only this type of skin testing can adequately treat all antigens to which the patient is sensitive. These differences in testing and vial mixing are explained.

The last form of therapy is surgical therapy, which corrects the obstructive phenomenon caused by allergic rhinosinusitis. The procedures described are reduction inferior turbinectomies and endoscopic sinus surgery.

It is felt by the authors that the specialist who is uniquely positioned to offer a patient suffering from allergic rhinosinusitis all three forms of therapy is the rhinologist.