Taking homeopathic medication does no harm (exception below) by itself, that's correct I wrote above. I'd like to correct myself. It may be right for a big majority of cases but in rare cases there seem to be exceptions.

Ernst, Edzard. 1996. Direct Risks Associated with Complementary Therapies. In E. Ernst (ed). Complementary Medicine: An Objective Appraisal. Butterworth, p. 113 (references in there) writes:

After repeated dilution's, varying concentrations of the original substance can still remain. Potentially toxic concentrations of arsenic (Kerr and Saryan, 1986) and cadmium (De Smet, 1992) have been found in homoeopathic preparations, and one case of an acute pancreatitis following the administration of a complex homoeopathic remedy (Kerr, 1986) has been reported. Low potency preparations can also cause allergic reactions: several such reports have been published (e.g. Van Ulsen, Stolz and Joost, 1988; Forsman, 1991). In view of such findings interactions with other treatments are conceivable in concomitant drug treatments, although there is no published evidence for or against this occurring.

Wolfgang