Orally administered decongestant drugs in disorders of the upper respiratory passages: a survey of clinical results

The links between allergy and otitis media with effusion

PURPOSE OF REVIEW

In this review we will examine evidence indicating that allergic inflammation is present in middle ear effusion. We will also discuss several of the problems relating to the diagnosis of allergy and allergic sensitization, and why anti-allergy treatments have been unsuccessful. This will provide a rationale for future studies in the field linking allergic inflammation with otitis media with effusion.

RECENT FINDINGS

Recent findings in atopic children demonstrated higher levels of eosinophils, T lymphocytes, and interleukin-4+ and interleukin-5+ cells compared with nonatopic patients. T-helper 2 cells and cytokines were found not only in middle ear effusions in atopic children but also in specimens from adenoid tissue. This demonstrates a strong correlation between allergic reaction in the middle ear and the upper airway.

SUMMARY

In summary, as our knowledge of the allergic and nonallergic influences on inflammation broadens, the paradigms of treatment may be altered. The accumulating experimental and clinical data suggest that it may be wiser to screen every child with otitis media with effusion for allergic rhinitis and ultimately to manage those with allergic inflammation differently to nonatopic individuals with otitis media with effusion.

Effects of sustained-release oral phenylpropanolamine on the nasal mucosa of healthy subjects

Phenylpropanolamine (PPA) is widely used as a nasal decongestant administered orally in sustained release preparations and, in Sweden, the recommended dose nowadays is 50 mg twice daily for adults. The aim of this placebo-controlled, cross-over study was to determine the onset and duration of the decongestive effect of 50 and 100 mg PPA in 15 healthy subjects. All subjects arrived at the laboratory at 07.30 h. After an acclimatisation, the nasal mucosal baseline was established with rhinostereometry and the minimal cross-sectional area was measured using acoustic rhinometry. The systolic and diastolic blood pressures were also determined. Then all subjects were given their study drugs for the day and the measurements were repeated every hour for 8 h. This procedure was repeated for 3 days at 48 h intervals between the days. For purposes of comparison, the decongestive effect of oxymetazoline nasal spray was studied on a separate day. The decongestive effect of 100 mg PPA was similar to that of topical oxymetazoline. It develops after 1 h and lasts for approximately 6 h. The decongestive effect of oxymetazoline was significantly greater than that of 50 mg PPA and that of 100 mg PPA was significantly greater than that of 50 mg PPA using rhinostereometry, but not when using acoustic rhinometry. However, 50 mg PPA had no significant decongestive effect, compared with placebo, with rhinostereometry or acoustic rhinometry. In the first 3 h after administration of PPA, there was a dose-response increase in the systolic and diastolic blood pressures, which then returned to baseline. In conclusion, this study shows that PPA in double the recommended dose, i.e. 100 mg, has a significant decongestive effect on the nasal mucosa in healthy subjects. However, when the dose of PPA is increased the systolic and diastolic blood pressures also increase.

Drug-Induced Changes in Eustachian Tube Function

Many studies have shown that antihistamines and decongestants are of little use in the treatment of acute otitis media and otitis media with effusion, or in the prophylaxis of these disorders.1 However, because some drugs can improve otitis media with effusion (glycocorticosteroids)2–4 and some can impair the opening function of the eustachian tube (atropine),5 it seems justified to continue studies of eustachian tube function and medication.

Treatment of allergic rhinitis

An increased understanding of the pathophysiology of allergic rhinitis can provide a logical basis for improved therapeutic strategies tailored individually to each patient. The first recommendation is the avoidance of possible or verified allergens. If this does not provide significant relief or is impractical, then immunotherapy plays a preventative role in some patients and it has been shown to be effective in certain cases. Initially, most patients try new nonsedating antihistamines, sometimes combined with a short course of topical vasoconstrictors. When nasal obstruction is a problem, a steroid spray is preferred. It is often necessary to add topical treatment for eye symptoms, e.g. antihistamine or cromoglycate eyedrops. In severe cases simultaneous administration of nasal corticosteroids and nonsedating antihistamines may achieve optimal control of symptoms. Cromolyn derivates are also effective in mild or moderate rhinoconjunctivitis and are especially recommended in the treatment of children. Systemic corticosteroid therapy should be reserved for the rare patient with extreme symptoms, and limited to short courses. Recent studies have shown that if patients are provided with appropriate medication, education and instruction, symptoms of allergic rhinitis can be well controlled with minimum impairment of quality of life.

The use of intranasal anticholinergic agents in the treatment of nonallergic perennial rhinitis

Nonallergic perennial rhinitis is a heterogenous disorder. Although the underlying cause is unknown, there is evidence of an autonomic imbalance with parasympathetic hyperreactivity in affected persons. We review this evidence and the role of ipratropium bromide, an anticholinergic drug with topical activity, in the management of nonallergic perennial rhinitis. The pharmacologic features, safety, and efficacy of ipratropium bromide are reviewed.

Recent advances in the treatment of otitis media

Otitis media (OM) continues to be a major cause of morbidity in infants and children. Antibiotics are presently the mainstay of treatment. A variety of agents including vaccinations against the most common causative organisms, prednisone, non-steroidal anti-inflammatory agents, intravenous immune globulin, antihistamines, decongestants, and topical antibiotics have been investigated. This review will address the recent developments in the treatment and prevention of OM.

Allergic rhinitis

Allergic rhinitis is a common disease with characteristic symptoms affecting the eyes, ears, and face as well as the nose. A detailed history is the foundation of a correct diagnosis. Laboratory tests may be needed to supplement this in atypical presentations. A combination of pharmacotherapy, immunotherapy, and environmental control may be required to control and prevent symptoms.

Surfactant and isoprenaline effect on eustachian tube opening in rats with acute otitis media

Purulent otitis media was induced in 12 middle ears of Sprague-Dawley rats by inoculation of pneumococci type 3. The pressure required to open the eustachian tube was recorded 4 days later and was found to be 3.05 +/- 0.10 kPa (mean +/- SEM), which was 1.08 +/- 0.15 kPa lower than the mean value obtained in a control group of healthy rats (P less than or equal to .001). We also measured the effects of pulmonary surfactant instilled into the middle ear as well as isoprenaline injected intravenously. The presence of surfactant further reduced the pressure opening level by 0.72 +/- 0.05 kPa; this reduction did not differ from that found in the control group (P greater than .8). Isoprenaline reduced the pressure opening level in the control group by 0.20 +/- 0.03 kPa (P less than or equal to .001), and no reduction was found in the rats with otitis media. Although the part played by surface tension-lowering factors in eustachian tube function is still uncertain, such factors apparently also exert an effect in the inflamed tube. However, isoprenaline, which is considered to act by the secretion of surface tension-lowering substances, did not facilitate opening of the eustachian tube in rats with acute otitis media.

The effect of gestation on eustachian tube function in rats

Patulous Eustachian tube (tuba aperta) is a distressing condition for the patient with such symptoms as autophony and a sensation of fullness in the ear. One-third of women with the diagnosis are pregnant or taking oestrogens. To study whether opening of the Eustachian tube is facilitated during pregnancy, the tube opening function of 14 pregnant rats was compared with that of 14 non-pregnant controls. The middle ear air pressure at which the tube opened (the pressure opening level, Pol) was lower in pregnant rats than in controls; and the difference between Pol and the pressure during open tube (at continued air injection) was less in the pregnant rats. In two additional rats it was then demonstrated that instillation of a surface tension lowering substance in the middle ear caused similar pressure changes as occur during pregnancy. It is concluded that opening of the Eustachian tube in rats is facilitated in pregnancy, and it is suggested that this is due to a reduction in surface tension of the Eustachian tube secretion.

Effects of phenylpropanolamine on ostial and nasal airway resistance in healthy individuals

Ostial airway resistance (OAR) of 11 maxillary ostia and the airway resistance of the nasal cavity (NAR) in 6 healthy persons were tested before and after administration of phenylpropanolamine (Ppa) and placebo. The effects of physical exercise were also tested. After logarithmic transformation, the resistance values showed a normal distribution. Significant effects on the ostial resistance in relation to initial values were found after Ppa medication. The effect was more pronounced in recumbency than in the sitting position. Physical exercise also gave a significant reduction of ostial resistance while placebo treatment was without effect. On comparison of the Ppa- and placebo-groups in an extended statistical analysis, more striking differences were found both for OAR and NAR. In this model study, Ppa thus showed effects in healthy individuals.