Seawater, With a Grain of Salt

Washing the nasal passages with a saline solution is better than OTC cold meds both at treating and preventing common colds, according to a study published in the January 2008 Archives of Otolaryngology-Head and Neck Surgery. After describing this study, I’ll also discuss briefly the concern I’ve been asked about regarding preservatives in some saline solutions.

This study included over 400 children of elementary school age who were randomly assigned to get either standard OTC meds or standard OTC meds plus a nasal wash. They were followed when they caught a cold, and for the rest of the winter. The saline wash, in this study, was processed from Atlantic Ocean seawater, so it had more minerals in it than just salt.

At the beginning of the study, children in the two groups had, on average, similar scores on nasal secretion amount and type, nasal obstruction, sore throat, cough, expectoration, sneezing, itching, and loss of taste or smell. At the first follow-up, the children who received the nasal wash had significantly less nasal secretion, clearer nasal secretion when present, less nasal obstruction, and were less likely to have a sore throat. They had also been less likely to take oral decongestant medications, even though they were available to both groups. There were few complaints from the kids about the wash. Continuing to use the wash resulted in fewer colds, fewer missed school days, and less use of medication for the rest of the winter.

This study relied on people’s reporting of cold symptoms rather than on objective observation. And the people in the study knew which children were getting the wash and which were not, which could introduce subtle bias. These factors raise questions about the results. But the results were consistent across eight different pediatric clinics. They were also consistent with the results of a 2007 objective analysis of eight other clinical trials which concluded that topical nasal saline improves the symptoms of chronic congestion and chronic sinusitis, whether used alone or in combination with other remedies.

A number of parents have asked me recently about the preservative benzalkonium chloride found in some saline solutions. There have been recent placebo controlled prospective studies suggestion a link between ongoing chemical preservative intake and hyperactivity — but the amount in short-term saline drop use is tiny compared to what most kids get in the diet. More to the point, though, in some people benzalkonium has been linked to rhinitis medicamentosum — a stuffy nose from the medicine. It’s been implicated as a possible cause of the rebound congestion from people using nasal decongestant sprays for more than 3-5 days. Other studies suggest that the chemical damages the lining of the nose. There have been at least 18 studies on the safety of this ingredient, with inconclusive results.

For most children, I don’t think this a big deal, but why use it if you don’t need to? You don’t even need to make your own saline solution or go to a natural products store. With my last cold, I picked up a product called Baby Simple Saline at a national drug store chain. It’s preservative free, creates a pleasant gentle mist, and comes in a container that can stay sterile after opening without a preservative.

References:
Slapak I, Skoupa J, Strnad P, and Hornik P. Efficacy of isotonic nasal wash (seawater) in the treatment and prevention of rhinitis in children. Arch Otolaryngol Head Neck Surg. 2008;134(1):67-74.
Harvey R, Hannan SA, Badia L, Scadding G. Nasal saline irrigations for the symptoms of chronic rhinosinusitis. Cochrane Database of Systematic Reviews 2007, Issue 3.
McCann D, Barrett A, Cooper A, Crumpler D, Dalen L, Grimshaw K, Kitchin E, Lok, K, Porteous L, Prince E, Sonuga-Barke E, Warner JO, and Stevenson J. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. The Lancet. 2007; 370:1560-1567.
Graf P, Hallen H, and Juto JE. Benzalkonium chloride in a decongestant nasal spray aggravates rhinitis medicamentosa in healthy volunteers. Clin Exp Allergy.1995; 25:957-965
Marple B, Roland P, Benninger M. Safety review of benzalkonium chloride used as a preservative in intranasal solutions: an overview of conflicting data and opinions. Otolaryngol Head Neck Surg, 2004; 130:131-141.