Quality assessment of Andrographis paniculata products reveals significant labelling inaccuracies and contaminations

Abstract

BACKGROUND: Andrographis paniculata products have gained in popularity for the management of respiratory infections since the COVID-19 pandemic. None of these products holds marketing authorisation and all are sold as herbal food supplements. Current herbal food supplement regulations generally do not impose quality assessments prior to commercialisation, such that the quality of herbal food supplements available to consumers is largely un-known. STUDY AIM: To assess the quality, purity and labelling accuracy of A. paniculata-containing products, focusing on andrographolide content (the pharmaceutically active component) and the presence of contaminants and residues. METHODS: Forty A. paniculata-containing products were purchased from 13 countries: 13 from pharmacies and 27 from online retailers readily accessible to consumers in Switzerland. Samples were analysed using ultra-high-per-formance liquid chromatography–ultraviolet (UHPLC-UV) and ultra-high-performance liquid chromatography–mass spectrometry (UHPLC-MS) based on the European Phar-macopoeia method. Contaminants and residues were as-sessed using inductively coupled plasma mass spectrom-etry and gas chromatography–mass spectrometry, respec-tively. RESULTS: All samples except one contained A. panic-ulata. The measured daily dose of andrographolide was compared to the labelled dose. Andrographolide content ranged from 29% to 174% of the labelled dose, with only 2 products accurately labelled, while 20 were underdosed and 1 overdosed. Two products contained quercetin, which interfered with UHPLC-UV analysis. Additionally, three online-purchased products contained toxic contam-inants, including a heavy metal (mercury) or pesticides (strychnine, butralin). CONCLUSION: This study reveals widespread misla-belling and underdosing in A. paniculata-containing food supplements marketed internationally, along with the pres-ence of impurities that pose risks to consumers in products bought online. Regulatory authorities must implement stringent quality controls to ensure consumer safety and product transparency.