Andrographis paniculata has a long history of traditional use in Ayurveda and Traditional Chinese Medicine for treating various infections, including fevers and respiratory illnesses. In recent decades, it has been studied scientifically for its potential effectiveness against upper respiratory tract infections, including influenza.

Several randomized controlled trials and systematic reviews have examined standardized extracts of Andrographis (often in combination with other herbs) for treating symptoms of influenza and the common cold. The active constituent, andrographolide, is proposed to exert antiviral, anti-inflammatory, and immunomodulatory effects. Some studies have shown that Andrographis can reduce the severity and duration of symptoms such as sore throat, cough, and nasal congestion compared to placebo. A 2017 Cochrane review of herbal treatments for the common cold found moderate evidence that Andrographis may be more effective than placebo for reducing symptom severity, though influenza-specific trials remain limited.

Despite promising findings, most studies are small, heterogeneous, and often combine Andrographis with other botanicals, making it difficult to isolate its effect on influenza specifically. Safety appears acceptable for short-term use. Overall, scientific evidence supports some benefit of Andrographis for respiratory infections, including influenza, but higher-quality, influenza-specific clinical trials are needed to confirm efficacy.