Formulation and Evaluation of Herbal Gel Using Betel Leaf (Piper betle L.) Extract

Betel leaf (Piper betle L., family Piperaceae) has been chewed, applied and prescribed in India and South-East Asia for many centuries. Its leaves carry a volatile oil rich in phenolic compounds, mainly hydroxychavicol, chavibetol and eugenol, along with tannins, flavonoids and alkaloids, and these constituents are linked to antibacterial, antifungal, antioxidant, anti-inflammatory and wound healing properties. Topical use of the crude leaf is messy and its dose is not controlled, so converting the extract into a proper dosage form is a practical need. A gel is a good choice because it spreads easily, feels cool, washes off with water, is non-greasy and can carry a plant extract without difficulty. This review collects the available information on the botanical profile and chemistry of betel leaf, the extraction techniques used, the gelling agents and excipients selected for herbal gels, the method of preparation, and the evaluation parameters used to judge quality, safety and activity. Published formulation studies are summarised and the gaps that still need attention, such as standardisation of the extract, long term stability and clinical confirmation, are discussed.