Antitussive Efficacy of Dextromethorphan in Cough Associated with Acute Upper Respiratory Tract Infection

Abstract

Dextromethorphan is one of the most widely used antitussives for the treatment of cough associated with acute upper respiratory tract infection. However, there is very little data to support the efficacy of dextromethorphan in this disease state. This aim of this study was to obtain more information about the efficacy of a single dose of 30 mg dextromethorphan in the treatment of cough associated with acute upper respiratory tract infection. The study was a double-blind, stratified, randomized and parallel group design. Both objective and subjective measurements of cough were recorded over 10-min recording periods in a quiet room before (baseline) and at 90, 135 and 180 min after treatment. Forty-three patients (30 females and 13 males), mean age 22.9 years (range 18-46 years), with acute dry or slightly productive cough and otherwise healthy were included in the study. Patients were randomized to placebo treatment (n = 22) and dextromethorphan treatment (n=21). The results showed similar trends in both treatment groups with statistically significant reductions (P < 0.05) in cough sound pressure level (CSPL), cough frequency (CF) and subjective scores for cough severity within treatment groups but little difference between the treatment groups during the study period. The only statistically significant difference between treatment groups was for the mean CSPL changes from baseline to 90 min (P=0.019). There was a significant positive correlation between CSPL and CF (r = 0.752, P= 0.000) for changes in cough measurements from baseline to 90 min after treatment and this indicates that CSPL may be a useful measure of cough severity. This study provides very little if any support for clinically significant antitussive activity of a single 30 mg dose of dextromethorphan in patients with cough associated with acute upper respiratory tract infection.

Objective measurement of cough in otherwise healthy volunteers with acute cough

“…It is known that more females present to general practice with coughs secondary to URTI [34], which may also explain the excess of females presenting for inclusion in this study. Indeed other studies of treatments for acute cough have often recruited a similar proportion of females [36][37][38]. Finally it remains to be seen whether limiting recruitment to patients earlier in the natural history of colds has any significant impact on the variability and repeatability of cough frequency.…”

Effect of Dextromethorphan, Diphenhydramine, and Placebo on Nocturnal Cough and Sleep Quality for Coughing Children and Their Parents

“…[8][9][10][11][12][13] Objective assessments of DM in adults with URI also have had conflicting results. [14][15][16] DPH is generally thought to be ineffective when compared with PL for the treatment of acute cough as a result of URIs, [17][18][19] but some reports contradict this belief. 20,21 DPH is widely accepted as an effective sedative.…”

Analysis of the evidence of efficacy and safety of over-the-counter cough medications registered in Brazil

“…Furthermore, the present study included phytopharmaceuticals, unlike the study performed in the 1980s. et all, 1986Taylor et al, 1993Lee et al, 2000Paul et al, 2004Paul et al, 2007Pavezi, et al, 2001 Randomized Clinical Trial SIETES Paul et al, 2007 Literature Review SIETES Thanacoody, 2007 Regarding the therapeutic classes of the formulations registered in Brazil according to ATC level 4 (Table I), there is a prevalence of other combinations for cough treatment (60.0%), but the following classes are also included: expectorants (15.0%), mucolytics (10%) and other cough suppressants (10%). The most frequent type of combination involves synthetic drugs (47.5%), but there are also combinations of phytopharmaceuticals and synthetic drugs (12.5%) as well as phytopharmaceuticals (2.5%).…”