The dorsal marginal rabbit ear vein was injected with 0.25 ml of 0.1% or 0.25% sodium tetradecyl sulfate (STS) (Sotradecol Injection) or undiluted or 50% Scleremo (Scl) (chromated glycerin). Only the 50% Scl solution failed to produce clinical or histologic thrombosis at 1 hour. Clinical fading was observed in STS-treated vessels at 10 days postinjection. Histologically, early thrombus formation with focal endothelial necrosis was replaced by fibrosis and microangiopathic recanalization. Although undiluted Scl caused similar, yet milder histologic findings, luminal recanalization after 10 days resulted in a clinically unfaded vessel. The use of 50% Scl produced no endothelial damage with no subsequent change in vessel appearance. Cutaneous necrosis or extravasation of erythrocytes was not observed.