Long Dan (Gentiana scabra): Benefits, Dosage, Safety & Evidence

Questions fréquentes

How does Long Dan work in the body?

Long Dan (Gentiana scabra) works primarily through its iridoid glycosides, particularly gentiopicroside and swertiamarin, which provide hepatoprotective and anti-inflammatory effects. These compounds, along with xanthones, help clear heat and drain dampness from the liver and gallbladder channels according to traditional Chinese medicine principles. The herb's extreme bitterness stimulates digestive secretions. Evidence level C supports these mechanisms, based primarily on in vitro and animal studies rather than large-scale human trials.

Does Long Dan interact with any medications?

Long Dan may interact with hypoglycemic medications due to its blood sugar-lowering effects, potentially causing additive hypoglycemia. Patients taking diabetes medications should monitor blood glucose closely and consult a healthcare provider. The herb's effects on liver metabolism could theoretically alter the pharmacokinetics of drugs metabolized by hepatic enzymes. Those on anticoagulants or immunosuppressants should exercise caution. Evidence level C indicates limited clinical interaction data, so patients should inform their healthcare provider of all supplements.

What is the recommended dosage for Long Dan?

The standard adult dosage for Long Dan is 3–6 grams of dried root prepared as a decoction daily. For standardized extracts, 200–400 mg taken twice daily is commonly recommended. Dosage should be adjusted based on individual constitution and condition severity. This herb is extremely bitter and is typically taken in formula combinations like Long Dan Xie Gan Wan rather than alone. Long-term use is contraindicated. Evidence level C supports these traditional dosing guidelines.

Is Long Dan safe during pregnancy?

Long Dan (Gentiana scabra) is contraindicated during pregnancy and is considered unsafe. The herb's bitter, cold nature and its effects on the liver and gallbladder channels make it inappropriate for pregnant women. Additionally, its potential hypoglycemic effects and uterine-stimulating properties pose risks to fetal development. Women who are breastfeeding should also avoid this herb. Evidence level C, based on traditional contraindications and pharmacological rationale, supports avoiding Long Dan during pregnancy.

What is Long Dan used for in traditional Chinese medicine?

In traditional Chinese medicine, Long Dan is primarily used to clear heat and drain dampness from the liver and gallbladder channels. It treats conditions including acute eye disorders with heat signs, genital conditions from damp-heat, jaundice, and bitter taste in the mouth. It is a key ingredient in the classic formula Long Dan Xie Gan Wan. The herb's hepatoprotective properties make it valuable for liver support. Evidence level C supports these traditional uses, based on historical application and preliminary research.

What are the side effects of Long Dan?

Long Dan may cause gastrointestinal irritation and nausea, particularly when taken in excess or on an empty stomach. Its bitter, cold properties can worsen cold constitution and spleen qi deficiency symptoms such as loose stools, fatigue, and poor appetite. Hypoglycemia has been reported, especially in susceptible individuals. Long-term use is contraindicated due to potential damage to spleen and stomach qi. Those with cold conditions or weak digestion should avoid this herb. Evidence level C supports these safety considerations.

Fiche d'information compilée à partir de PubMed

Cette fiche a été compilée à partir de résumés PubMed (NIH) avec l'assistance d'une IA. Chaque affirmation factuelle est citée par un article PubMed réel (voir la liste des sources). Elle n'a pas encore été révisée par un humain — confirmez auprès d'un professionnel de santé avant utilisation.

Compilé à partir de 30 articles PubMed · modèle : gemma4:31b

Résumé

Long Dan (Gentiana scabra) is a traditional Chinese medicinal herb used for treating inflammation, liver diseases, and skin conditions [PMID:28510889, 30630090].

Contexte

Gentiana scabra Bunge, known as Longdan in Chinese, is a perennial herb of the Gentianaceae family whose dried roots and rhizomes are used in East Asian medicine [PMID:32182812, 41084165].

Usages traditionnels

It has been used for over 2000 years to treat inflammation, anorexia, indigestion, and gastric infections [PMID:28510889, 28510924]. It is also used for heat-clearing, damp-drying, and treating skin diseases caused by wind-heat or dampness-heat [PMID:32182812, 30630090].

Composés actifs

Key bioactive compounds include secoiridoid glycosides such as gentiopicroside, swertiamarin, and loganic acid [PMID:28510924, 25280952]. Other identified constituents include triterpenoids [PMID:11937156, 39447985], benzoate glycosides [PMID:38972439], and the alkaloid gentianine [PMID:41371563].

Mécanisme d'action

Gentiopicroside modulates NF-κB and MAPK signaling pathways to suppress pro-inflammatory cytokines and activates the Keap1-Nrf2 pathway to enhance antioxidant defenses [PMID:41378205]. Gentianine interacts with KDM5B to induce ferroptosis in renal cell carcinoma cells [PMID:41371563]. Gentiana scabra extract may regulate the TLR4/NF-κB pathway in alcoholic liver disease [PMID:38062827] and the TBK1 pathway in non-alcoholic fatty liver disease [PMID:35115947].

Preuves cliniques

Preuve AHerpes Zoster

A modified Gentiana formula resolved pain earlier than pharmacotherapy alone and lowered the incidence of postherpetic neuralgia [PMID:28078812].

Preuve AInsomnia

Long Dan Xie Gan Tang (LDXGT) has been clinically validated for effectiveness and safety in treating insomnia, particularly with bad-tempered symptoms [PMID:32176067].

Preuve DIschemic Stroke

Huang-Qi-Long-Dan Granule (HQLDG) significantly decreased infarct volume and improved behavior and brain pathology in mouse models [PMID:38782148, 41861685].

Preuve DAlcoholic Liver Disease

Gentiana scabra extract demonstrated liver protection effects by regulating the TLR4/NF-κB pathway in mice [PMID:38062827].

Preuve DContact Dermatitis

Ethanol extract of G. scabra roots and rhizomes alleviated skin lesions and thickness in mice [PMID:30630090].

Sécurité et effets indésirables

Long Dan Xie Gan Tang has been identified as a TCM product with potential hepatotoxicity [PMID:26357619, 24844799].

Interactions médicamenteuses

Potential herbal formula-drug interactions are noted as an essential issue during the administration of formulas like Long-Dan-Xie-Gan-Tang [PMID:28911662].

Synthèse des preuves

Evidence ranges from high-level systematic reviews for specific formulas (Herpes Zoster, Insomnia) to preclinical animal and in vitro studies for liver, stroke, and skin conditions.

Sources PubMed

1.PMID: 38782148 (2024) — Multi-omics approaches for the understanding of therapeutic mechanism for Huang-Qi-Long-Dan Granule against ischemic stroke. · Pharmacological research
2.PMID: 28078812 (2017) — Gentiana scabra Bunge. Formula for Herpes Zoster: Biological Actions of Key Herbs and Systematic Review of Efficacy and Safety. · Phytotherapy research : PTR
3.PMID: 11937156 (2002) — Triterpenoids from Gentiana scabra. · Phytochemistry
4.PMID: 41378205 (2025) — Therapeutic efficacy and mechanisms of gentiopicroside in various diseases. · Frontiers in pharmacology
5.PMID: 26357619 (2014) — Traditional Chinese Medicine Induced Liver Injury. · Journal of clinical and translational hepatology

Long Dan

Sources et citations

Calculer une dose sûre de Long Dan

Glycyrrhiza Glabra Var Persian

Carqueja

Vietnamese Coriander

Questions fréquentes

Résumé

Contexte

Usages traditionnels

Composés actifs

Mécanisme d'action

Preuves cliniques

Sécurité et effets indésirables

Interactions médicamenteuses

Synthèse des preuves

Sources PubMed

Sources gouvernementales

Long Dan

Sources et citations

Calculer une dose sûre de Long Dan

Plantes associées

Glycyrrhiza Glabra Var Persian

Carqueja

Vietnamese Coriander

Questions fréquentes

Résumé

Contexte

Usages traditionnels

Composés actifs

Mécanisme d'action

Preuves cliniques

Sécurité et effets indésirables

Interactions médicamenteuses

Synthèse des preuves

Sources PubMed

Sources gouvernementales