Patients with infection of the nose and throat of bacterial or viral etiology such as common cold and flu can present with a variety of sinonasal symptoms. These may include congested nose or rhinorrhea, nasal and sinus pressure as well as fever, anosmia, ageusia, presence of cough, and/or purulent nasal secretions. Colds are usually self-limited and last seven to ten days, although symptoms can endure up to three weeks. Symptomatic treatment includes pharmacological medications and/or over-the-counter medicines aiming to reduce symptoms while improving the quality of life.

Nasal irrigation is recommended as an adjunctive treatment for ENT disorders. Nasal lavage with hypertonic saline/seawater was shown to have a favorable effect in the management of sinonasal conditions and symptoms [1,2]. Among different hypertonic solutions, seawater solutions of 2.3% NaCl are frequently used in adult and pediatric populations [3-5].

Additional ingredients have been introduced to sinonasal irrigation fluids to improve their action and/or provide additional ancillary benefits. These may include algal or plant extracts, essential oils, vitamins, hydrating agents or other ingredients. In the current user survey, the nasal irrigation solution is a hypertonic seawater solution (2.3% NaCl) comprising algal and herbal ingredients (HSS-Plus). Two families of additional ingredients are introduced to HSS-Plus, namely: I) algal extracts from Undaria pinnatifida and Spirulina platensis. These ingredients have been shown to possess interesting biological actions including, among others, anti-oxidant, anti-inflammatory, anti-viral and hydrating properties when administered systemically in animal models or humans [6]. Of particular interest for topical applications are barrier and hydrating properties contributed by these ingredients. Specifically, marine seaweed polysaccharides, such as fucoidan from Undaria pinnatifida, have been found to inhibit influenza, parainfluenza, avian influenza strains and herpes viruses [7,8]. Experimental results have also shown that fucoidan from Undaria pinnatifida inhibits viral entry of SARS-CoV-2 [9]. A similar mechanism of adhesion blockage has been reported for bacteria [10] arguing for a general barrier role of the ingredients against pathogens. Finally, the ingredients exhibit hydrating properties as based on their capacity to absorb moisture [11]. HSS-Plus further comprises a second family of ingredients: II) herbal ingredients from Eucalyptus globulus, Mentha spicata, and Thymus vulgaris. These ingredients also possess interesting systemic properties [12-14]. However, they are only expected to provide a refreshing olfactory sensation at low concentrations [15].

To obtain clinical data with HSS-Plus in order to evaluate its efficacy and safety, a user survey study was conducted assessing its ability to alleviate respiratory symptoms in patients with ENT disorders within the scope of routine care in real-life.