Homeopathy uses drugs in extreme dilutions that are mostly devoid of the original drug molecules. Drug-induced water structures are thought to be responsible for their therapeutic effect. We have already observed that homeopathic potencies first interact with serum albumin, which is present in the oral mucosa. In this experimental study, we have shown that the homeopathic potencies of three drugs, Bryonia alba (Br), Rhux toxicodendron (Rt), and Thuja occidentalis (Th), initiate their action on Human Serum Albumin (HSA). The potency-HSA complexation has been observed by electronic spectroscopy. The control, HSA plus water, shows only one peak at 216 nm, but the potencies plus HSA show two peaks, one at 205 nm and another around 265 nm. The first peak is due to the peptide bond. The first peak in the control shows a marked red shift. The second peak at higher wavelength is due to the aromatic amino acids. The first peak with the potencies shows a marked blue shift, possibly due to a change induced by the potencies on the peptide bond. Unlike water control the potencies interact with aromatic amino acids. It is evident that the complexes made up of HSA and potency are different from those of the control. This means that homeopathic potencies are not ordinary water. It is concluded that water control interacting with HSA shows a single peak in UV-spectra at lower wavelength, but homeopathic potencies show one additional peak at a higher wavelength besides the peak at the lower wave length. HDs can produce effects on aromatic amino acids. The mother tinctures and their HDs show marked differences from each other in their electronic spectra.