Journal of Dental Research, Vol 73, 620-628, Copyright © 1994 by International & American Associations for Dental Research Online Journals
DMSA administration to patients with alleged mercury poisoning from dental amalgams: a placebo-controlled study
G. Sandborgh Englund, R. Dahlqvist, B. Lindelof, E. Soderman, B. Jonzon, O. Vesterberg and K. S. Larsson
Department of Odontological Toxicology, Karolinska Institute, Huddinge, Sweden.
The present investigation was performed to determine the effect of 14-day
oral administration of meso-2.3-dimercaptosuccinic acid (DMSA) on the
urinary mercury excretion and the potential reduction of blood and plasma
mercury concentrations, and also to relate these effects to possible
decrease of symptoms, allegedly associated with amalgam fillings. Twenty
subjects, relating their symptoms to mercury from amalgam fillings,
received 20 mg/kg DMSA or placebo for 14 days. Their symptoms and mood
states were recorded during the study and at a check-up 3 months later.
Interpretation was based on intra-individual differences. DMSA-treatment
resulted in an average increase in urinary mercury excretion by 65% and a
decrease in blood mercury levels of 0.04 microgram/L/day. At the check-up
after 3 months, urinary mercury excretion had returned to the pre-treatment
level. No treatment effect of DMSA was apparent on subjective symptoms and
mood state. One statistically significant treatment effect was noted-a
decrease in fatigue-inertia in the DMSA-group-but there was no demonstrable
correlation with increased urinary excretion or decreased blood
concentration of mercury. Three subjects showed hypersensitive reactions,
probably DMSA-specific, at the end of the treatment period. This
placebo-controlled study provides no scientific support for diagnostic or
therapeutic administration of DMSA for symptoms allegedly associated with
chronic mercury exposition from dental amalgam fillings.
