The numbers of those with sinusitis have risen by around 25% in recent years. This is thought to be due to lifestyle factors and environmental pollution, and is in line with the rising prevalence of allergies in general. Sinusitis is far more than a blocked nose; it can have quite an effect on daily quality of life and on sleep, and is implicated in other conditions such as asthma, sleep apnoea, nasal polyps, and allergic irritability syndrome in...