The effects of calcium dobesilate on acute lymphedema (with and without macrophages), and on burn edema.

Calcium dobesilate ("Doxium", O.M. Laboratories, Geneva) was tested in two high-protein edemas. While at a high dose level it had no effect on burn edema of the ratfoot, it did at a low dose. It greatly reduced (to 26%) acute lymphedema in the rat thigh (although not in the foot). Electron microscopy confirmed these findings, and showed that the drug increased the number of macrophages in the tissues and reduced the protein concentrations. If, however, the macrophages were destroyed (by silica) this effect on acute lymphedema was lost (as with benzo-pyrones). Calcium dobesilate also reduces high-protein edemas in other models, and in many ways its actions resemble those of benzo-pyrones. Hence it is suggested that this substituted benzene ring may be the basic structure responsible for this action in high-protein edema, and that the pyrone ring (and any side-chains) in the benzo-pyrones are not essential to their enhancement of proteolytic activity by macrophages.