When levamisol was added to the antituberculosis therapy of rabbits with destructive pulmonary tuberculosis, intensive infiltration of the zone of lesions with polymorphonuclear cells and their accumulation in cavities, increased numbers of giant multinuclear cells, "macrophage" transformation of epithelioid cells were observed; the caverns had one-layer connective tissue wall or underwent scarring. In treatment with levamisol alone the same morphological features were observed, however, without complete disappearance of the signs of specific inflammation and abacillation in all the animals. The animals given antituberculosis therapy alone retained the signs of specific inflammation despite abacillation. Changes in inflammation morphology under the influence of levamisol characterize it as a histomodulator and indicate (considering cholinergic and thymomimetic effect of levamisol) a difference in biochemical and immunological mechanisms of chronic specific and acute nonspecific inflammation.