To determine if a single application of a vapor rub (VR) or petrolatum is superior to no treatment for nocturnal cough, congestion, and sleep difficulty caused by upper respiratory tract infection.
Surveys were administered to parents on 2 consecutive days—on the day of presentation when no medication had been given the previous evening, and the next day when VR ointment, petrolatum ointment, or no treatment had been applied to their child's chest and neck before bedtime according to a partially double-blinded randomization scheme.
There were 138 children aged 2 to 11 years who completed the trial. Within each study group, symptoms were improved on the second night. Between treatment groups, significant differences in improvement were detected for outcomes related to cough, congestion, and sleep difficulty; VR consistently scored the best, and no treatment scored the worst. Pairwise comparisons demonstrated the superiority of VR over no treatment for all outcomes except rhinorrhea and over petrolatum for cough severity, child and parent sleep difficulty, and combined symptom score. Petrolatum was not significantly better than no treatment for any outcome. Irritant adverse effects were more common among VR-treated participants.
In a comparison of VR, petrolatum, and no treatment, parents rated VR most favorably for symptomatic relief of their child's nocturnal cough, congestion, and sleep difficulty caused by upper respiratory tract infection. Despite mild irritant adverse effects, VR provided symptomatic relief for children and allowed them and their parents to have a more restful night than those in the other study groups.
Comments
Is there sufficient evidence for vapor rub use in the treatment of common colds?
We read with interest the recent report by Paul et al (1) in the December 2010 issue of Pediatrics regarding the use of Vapor Rub (VR) for nocturnal cough and cold symptoms. For over a century, many forms of medicated ointments (including those with camphor) have been used to relieve cough and cold symptoms without any scientific evidence to support their benefit. We, therefore, commend the investigators for conducting possibly the first study to evaluate the utility of such a common practice. However, we have several concerns regarding the methodology and conclusions from this study.
We believe it could be misleading to emphasize the “blinded” nature of this study. It is unlikely that the parents of the “no treatment” group were truly blinded since these parents received empty cups in the bag. Despite the study team’s effort, due to the distinctive aromatic and characteristic smell of VR we do not believe that even the parents of the VR and petroleum groups were successfully blinded, since 86% and 89% of the parents in these respective groups accurately reported which arm of the study they were in. Although the clinicians were blinded, they were not involved in the assessment of participant’s response to the intervention. Their data showed that all 3 treatment groups had improvements in all assessed areas. However, when the groups were compared, statistically significant difference was primarily observed between the VR and no intervention groups in cough frequency, cough severity and severity of congestion. Given the observed magnitude of these significant difference (the greatest difference of <1.5 on Likert-scale -change), it remains unclear whether these differences are also clinically meaningful, particularly since the subjects were not truly blinded.
Finally, we would like to remind readers of the potential danger of camphor containing products like Vapor Rub in children. We agree with the authors’ comment that most of the adverse events reported were associated with accidental ingestion rather than topical exposure. However, we recently reported a cluster of children with seizures caused by camphor poisoning, including topical use (2).
Based on the above issues, we recommend further investigation of the benefits and safety of vapor rubs. We feel that an implied message of significant medicinal properties for this product is misleading at this time.
Reference List
(1) Paul IM, Beiler JS, King TS, Clapp ER, Vallati J, Berlin CM, Jr. Vapor rub, petrolatum, and no treatment for children with nocturnal cough and cold symptoms. Pediatrics. 2010; 126(6):1092-1099
(2) Khine H, Weiss D, Graber N, Hoffman RS, Esteban-Cruciani N, Avner JR. A cluster of children with seizures caused by camphor poisoning. Pediatrics. 2009; 123(5):1269-1272
Conflict of Interest:
None declared
Vaporub is still not the answer
Dr. Paul's study (1) of the comparative effects of Vaporub, petrolatum and placebo on cold symptoms has so many deficiencies that I was disappointed there was no accompanying editorial; this article could be seriously misused by many parents and pediatricians. First, Dr. Paul is a paid consultant for Proctor and Gamble, maker of Vicks Vaporub. Second, the study was not blinded; and 100% of parents guessed correctly they were giving Vaporub. Third, the study was of only 44 children. Fourth, on a 7 point Likert scale of symptom severity, one must question the clinical significance of a difference of only 1-1.5 points between placebo and Vaporub. (i.e. on most symptoms, placebo parents judged severity going from a baseline of 5 to 4, and Vaporub from a baseline of 5 to 3). Is this worth the 46% adverse effects Paul et al found? (Coming from the era of Vaporub 'attacks' as a child, I remember the burning eyes and chest being worse than the cold). I fear Paul's conclusions will get into parent magazines, and we'll again see camphor poisonings; (40 cc being potentially fatal in a child < 6 years). And if parents misuse it on their infants, as they do other cold medicines, seizures can result, which Paul mentions only in passing.(2)
As after most first studies, it is very hard to reverse practice when larger studies, from unbiased researchers, come out negative--or don't come out, since so few negative studies ever got published.
A provocative article (3) recently discussed "declining results." This describes a definite phenomenon in which most subsequent studies show less --or no effect, and occurs above and beyond the well-known factor of regression to the mean. Many researchers have shown it: initially positive reports are usually not replicated.
Pediatricians must beware to not support parents using Vaporub based on an initial study using such questionable methods, lest we replace one poor treatment for colds (oral cough medicines), with another. As the PEDIATRICS article following Pauls' demonstrates, adverse effects from cough medications continue to occur even after AAP and FDA proscriptions and market withdrawal.
Virginia Feldman MD FAAP 11230 SW Collina Ave. Portland, Or 97219 Locums pediatrician Kaiser Permanente NW
1. Paul, Ian P, et al: Vapor Rub, petrolatum, and no treatment for children with nocturnal cough and cold symptoms. Pediatrics. 2010,126:1092 -99. 2. Shannon M, et al.Toxic seizures in children: case scenarios and treatment strategies. Pediatr-Emerg Care. 2003,19(3);206-10. 3. Lehrer, Jonah. The Truth wears off. The New Yorker.2010, Dec 13:52-57 4. Shehab, Nadine et al. Adverse events from cough and cold medications after a market withdrawal of products labeled for infants. Pediatrics. 2010, 126: 1100-07.
Conflict of Interest:
None declared