Cineole, also known as eucalyptol, is a natural organic compound found in a variety of aromatic plants, most notably eucalyptus species. Its use to support the sinuses and respiratory system is justified by a substantial body of scientific evidence. Multiple clinical studies have demonstrated that cineole exhibits significant mucolytic, anti-inflammatory, and bronchodilatory effects, which may help alleviate symptoms of sinusitis and other upper respiratory tract conditions.

Randomized controlled trials have found that cineole can reduce the severity and duration of symptoms in acute and chronic sinusitis. For example, a double-blind, placebo-controlled study published in Laryngoscope (2004) showed that patients with acute rhinosinusitis experienced significant symptom relief, including improved nasal patency and reduced headache, after oral administration of cineole. Other studies have highlighted cineole’s ability to decrease nasal congestion by reducing inflammation of the mucous membranes and improving mucus clearance.

The mechanism of action is believed to involve inhibition of cytokine production and modulation of inflammatory pathways, as well as direct effects on mucus viscosity. While more research could further clarify its optimal use and long-term safety, current evidence supports cineole as a scientifically validated agent to support the sinuses and respiratory health.