A double-blind, double-paired comparison, placebo-controlled study was undertaken to determine the optimal agent for sclerotherapy of spider telangiectasias of the lower extremities. Sodium tetradecyl sulfate 0.5%, polidocanol 0.25%, heparsal, and normal saline control were evaluated in terms of clinical effectiveness and patient acceptance. Although all of the agents, except for the control, were effective, polidocanol was found to have the fewest adverse reactions and afforded the greatest patient comfort.