The use of Malabar Nut Tree Leaf Extract (Justicia adhatoda, also known as Vasaka) for sore throat is primarily based on traditional medicine, particularly in Ayurveda and other South Asian healing systems. The leaves contain alkaloids such as vasicine, which have been attributed with expectorant, anti-inflammatory, and antimicrobial properties. In traditional practices, the extract or decoction of the leaves is commonly used to soothe sore throat, cough, and other respiratory complaints.

Some preclinical studies and in vitro research have shown that extracts from the Malabar Nut Tree possess antibacterial and anti-inflammatory activities, which could theoretically contribute to sore throat relief. However, robust clinical evidence—particularly randomized, controlled human trials—specifically supporting its efficacy for sore throat is limited. The traditional use is widespread and longstanding, and some pharmacological data provide a plausible rationale, but the direct scientific validation specific to sore throat is modest at best.

In summary, the use of Malabar Nut Tree Leaf Extract for sore throat is justified by traditional use, with some supporting pharmacological evidence, but lacks strong clinical trial data for this particular indication.