Qualitative and Quantitative Analysis of Adulteration in Selected Herbal Antimalarial Remedies Sold in Owerri, Imo State

Herbal antimalarial remedies are popular in South Eastern Nigeria, where malaria remains a significant public health burden. Concerns about adulteration of these products with undeclared conventional drugs, particularly chloroquine and artemisinin derivatives, have been raised by health authorities. This study conducted qualitative and quantitative analysis of ten herbal antimalarial remedies purchased from patent medicine vendors and open markets in Owerri, Imo State. Thin Layer Chromatography was used for preliminary detection of undeclared pharmaceutical actives, followed by UV-Visible spectrophotometric quantification of identified compounds. Standard solutions of chloroquine phosphate and artesunate were used as reference substances. Four of the ten products showed TLC profiles consistent with the presence of chloroquine, and quantification confirmed chloroquine concentrations ranging from 12 to 58 mg per dosage unit. No artemisinin derivatives were confirmed in any sample. Two products showed the presence of unidentified compounds not attributable to the declared herbal ingredients. These findings indicate a significant prevalence of adulteration and confirm risks of inappropriate dosing, drug resistance development, and medication errors among consumers self-treating with herbal antimalarials. Regulatory enforcement of market surveillance in Imo State is urgently needed. Keywords: adulteration, herbal antimalarials, TLC, chloroquine, Owerri.