Clinical trial of 3 days of treatment with oral pseudoephedrine for the common cold in the southern hemisphere.

BACKGROUND: Single-dose studies indicate that pseudoephedrine (PSE) provides moderate relief for congestion in coryza, but there is a lack of repeated-dose studies. METHODS: Two hundred sixteen subjects participated in this double-blind, randomized placebo-controlled trial over 3 days. Measurements included posterior rhinomanometry, acoustic rhinometry, and subjective measures of congestion using a categorical scale and visual analog scale (VAS). Treatment was with one 60-mg PSE tablet four times daily or matching placebo. RESULTS: After the first dose, PSE relative to placebo consistently showed small improvements for all objective assessments of nasal congestion. The prespecified primary efficacy outcome (day 1 nasal airway resistance area under the curve) was not significantly different between groups. PSE produced a 5.5% (p = 0.031) increase in total nasal volume for 0.5-3 hours after dosing. A pooled analysis of days 1 and 3 data showed a VAS score decrease of 7.0% (p = 0.072) for the 0.5- to 3-hour period on PSE. CONCLUSION: PSE showed small but nonsignificant improvements in objective assessments of nasal congestion relative to placebo after a single dose.

The Effect of an Interactive Tutorial on the Prescribing Performance of Senior Medical Students.

OBJECTIVES: To evaluate the effectiveness of small group tutorials in teaching senior medical students the requirements of prescription writing. DESIGN: Random allocation to interactive tutorial or didactic lecture with blinded evaluation. SUBJECTS: All 1999 6th year medical students, the University of Adelaide. RESULTS: The Tutorial Attenders (mean 13.3, SD 2.6) performed significantly better than the Lecture Group (mean12.2, SD 3.0) p=0.041 and the Non-attenders (mean10.7, SD 3.1) p=0.041 and the Non-attenders (mean10.7, SD 3.1) p= 0.001. The 13 individual OSCE items formed four logical subgroups, and the Tutorial Attenders performed significantly better in Prescription Writing in all comparisons. CONCLUSION: A single, one-hour interactive tutorial is likely to be the minimum amount of intervention that will be effective in improving prescribing skills.

Opening the nasal valve with external dilators reduces congestive symptoms in normal subjects.

BACKGROUND: We examined whether the use of two different external nasal dilator devices influenced the size of the nasal valve area and symptoms of nasal congestion. METHODS: This was a randomized blind-allocation, open three-way crossover study of Breathe Right, Side Strip Nasal Dilators, and placebo. We studied 12 healthy subjects (10 female, 2 male; age range 26-56 years). Measures of total volume and total minimum cross-sectional area were collected. Subjective symptoms were collected using a visual analog scale and an ordinal scale. RESULTS: With both products, there was significant increase in the size of the minimum cross-sectional area compared to placebo, p = 0.004. This is supported by the decrease in the subjective reports of congestion; on the visual analog scale, compared to placebo p = 0.012 and the ordinal scale, compared to placebo, p = 0.004. CONCLUSION: Both devices significantly increase the size of the nasal valve area and reduce congestion in normal subjects.

A randomized, double-blind, placebo-controlled trial of pseudoephedrine in coryza.

1. The aim of the present study was to assess the efficacy of pseudoephedrine in coryza. 2. In a double-blind, randomized, placebo-controlled design, 48 adults with acute coryza received a single oral dose of 60 mg pseudoephedrine (Sudafed; Pfizer Consumer HealthCare Group, Caringbah, NSW, Australia) or matching placebo. Before and after dosing, nasal airway resistance (NAR), nasal volume, the minimum intranasal cross-sectional area (MCA) and the symptom of nasal congestion were measured. 3. Pseudoephedrine produced a significant decrease in NAR (P = 0.005; 95% confidence interval (CI) 0.073, 0.383). Nasal volume increased, but this did not reach significance (P = 0.07; 95% CI -0.842, 0.034). There was no change in MCA and symptoms. 4. In conclusion, pseudoephedrine has a moderate effect in decreasing objective measures of nasal congestion in coryza.

Vasodepressor syncope and the diagnostic accuracy of the head-up tilt test with sublingual glyceryl trinitrate.

Thirteen syncopal subjects and thirteen asymptomatic controls were examined by head-up tilt (HUT) with and without sublingual GTN. Adding GTN to HUT improved the sensitivity of the test (8 % to 46%) but decreased specificity (100 % to 54 %).

Validation by fluid volume of acoustic rhinometry before and after decongestant in normal subjects.

To validate the measurement of nasal volume by acoustic rhinometry, acoustic rhinometry (AR) measures before and after decongestion were compared to a reference volume measurement in 10 healthy volunteers over 3 visits each. The reference method was hydraulic infusion with manometry, involving slow constant-rate infusion of isotonic saline into each nasal cavity while the subject was appropriately positioned. Consecutive 10 mm nasal segments were measured, and hydraulic volume derived. AR volume and hydraulic volume measures were compared. Within subject reproducibility of hydraulic volume and AR volume measures over 3 study days was better than 16% and 11%, respectively. Pre-decongestant, highly significant correlations between AR volume and hydraulic volume in the 20-40 mm segment were found. The mean ratios of AR volume/hydraulic volume ranged from 1.01-1.14. Post decongestant, significant correlations were found in the 30-50 mm segments. The mean AR volume/hydraulic volume ratios were significantly lower (0.88-1.03). Hence, the magnitude of the AR volume change after decongestant was less than the hydraulic volume change (ratio range 0.8 to 1.01), but there were still significant correlations between hydraulic volume and AR volume in the 20-50 mm segments of the cavity. Since hydraulic volume is expected to be similar to anatomical nasal volume, we conclude that changes in AR volume before and after vasoconstriction are similar to anatomical changes in nasal vasculature. AR volume measurements provide a sensitive, reliable and accurate assessment of vasoactive drugs in the nasal cavity.