RESUMO
BACKGROUND: Homeopathic drugs even with dilutions beyond 10(23) (high potencies) are frequently used, although their working mechanism is still unknown. Curative information preserved in solvent structure is postulated to exert biologic effects. OBJECTIVE: The objective was to test for a stimulating or inhibiting effect of high potencies of the homeopathic remedy HgCl2 (Mercurius corrosivus) on two sugar hydrolases. METHODS: High potencies were produced using stepwise dilution plus shaking. Controls included potentized solvent (aqua bidestillata), equimolar dilutions without shaking, and enzyme-free references. Tested were potencies with dilution factors 1:200 (CC) on diastase extract from winter barley, and 1:100 (C) on alpha-amylase from hog pancreas. Enzyme activity was colorimetrically determined by Lugol's iodine-starch reaction. RESULTS: An inhibiting effect of HgCl2 on enzyme activities was observed only in low potencies and dilutions. Statistically significant differences between potencies and controls were not found in randomized and blinded experiments. CONCLUSIONS: This experimental design provided independent reproducible results of cell-free in vitro assays. However, it did not indicate an effect of potentized HgCl2 on hydrolases. Demonstrating potency effects may require additional experimental features.