Longan Leaf

Longan leaf contains bioactive compounds including quercetin, ellagic acid, corilagin, and tannins that exhibit antipyretic and anti-inflammatory properties. These compounds are thought to work by inhibiting inflammatory mediators and reducing oxidative stress in the body. The tannins and flavonoids may also contribute to antimicrobial activity, which could help address underlying infections. However, the exact mechanism of action has not been fully established in human studies, and current evidence is limited to traditional use and preliminary research (Evidence Level C).

Longan leaf may interact with medications due to its tannin content, which can interfere with the absorption of certain drugs when taken simultaneously. There is potential for interaction with anticoagulant and antiplatelet medications, as quercetin may affect blood clotting. Additionally, the diuretic properties suggested by traditional use could potentially interact with diuretic medications or drugs affecting kidney function. Limited clinical data exists on specific drug interactions. Patients taking prescription medications should consult a healthcare provider before using longan leaf supplements (Evidence Level C/Traditional).

The traditional adult dosage for longan leaf is 3-6 grams of dried leaf per day, typically prepared as a decoction or tea. This dosage is based on traditional Thai and Chinese folk medicine practices rather than standardized clinical trials. There is insufficient clinical evidence to establish an optimal therapeutic dose. Dosage may vary depending on the specific preparation and intended use. Individuals should follow product labeling instructions or consult a qualified healthcare practitioner for personalized guidance (Evidence Level C/Traditional).

Longan leaf is considered unsafe during pregnancy and should be avoided. Traditional medicine sources contraindicate its use in pregnant women, though specific safety data is limited. The presence of bioactive compounds such as tannins and the herb's traditional use for stimulating certain physiological processes have not been adequately studied in pregnant populations. Women who are pregnant, planning to become pregnant, or breastfeeding should not use longan leaf preparations without medical supervision. Always consult a healthcare provider before using herbal remedies during pregnancy (Evidence Level C/Traditional).

Longan leaf may cause gastrointestinal upset, including nausea, stomach discomfort, or loose stools, particularly when taken in higher doses or on an empty stomach. The tannin content can contribute to digestive irritation in sensitive individuals. Allergic reactions are possible but uncommon. There is limited documentation of adverse effects in clinical literature. If side effects occur, discontinue use and consult a healthcare provider. Those with existing gastrointestinal conditions should exercise caution when using this herb (Evidence Level C/Traditional).