Exploring medicinal plants for antiparamphistomiasis: A scoping review of pharmacological insights and methodologies

Paramphistomiasis, a neglected infectious disease affecting ruminants, leads to significant productivity losses. The limitations of current antitrematodal agents and emerging anthelmintic resistance highlight the need for alternative treatments, including those derived from medicinal plants. Pharmacological screening plays a crucial role in the discovery and development of natural products for antiparamphistomiasis. This scoping review summarises the methodological aspects used in pharmacological screening studies of medicinal plants for antiparamphistomiasis. Eligible studies included original research articles involving in vitro, in vivo, and in silico methodologies, published in English without year restrictions. Studies focusing on diagnostics, epidemiology, synthetic agents, or feed supplementation were excluded. A systematic literature search was conducted in PubMed and Scopus using the keywords Paramphistomum, pharmacological screening, and medicinal plant research. The search, carried out between 11 December 2023 and 31 December 2024, identified 45 articles. Data were extracted using standardised tables covering the test compound, methodological aspects (study design, assay techniques, reporting standards), and study outcomes. A framework analysis categorised methodological element into inputs, processes, and outputs. The findings revealed that the test compounds included plant extracts, fractions, isolates, herbal preparations, and nanoparticles. Common screening methods included the Adult Motility Assay (AMA), Faecal Egg Count Reduction Test (FECRT), and molecular docking. However, considerable heterogeneity in study design, implementation, and reporting contributed to bias, particularly within in vivo studies. The review highlights the need for more integrated and standardised research frameworks to advance natural products as alternative therapies for antiparamphistomiasis.