Therapeutic levels of L-DOPA are achieved by orally administering a pharmaceutical effervescent-enteric coated tablet comprising:A. a member selected from the group consisting of L-DOPA or a derivative thereof capable of enzymatically cleaving and reverting to L-DOPA in vivo,B. a non-toxic pharmaceutically acceptable inert diluent,C. a non-toxic pharmaceutically acceptable carbon dioxide releasing agent,D. a non-toxic pharmaceutically acceptable effervescing agent, andE. a non-toxic pharmaceutically acceptable enteric coating.This composition is extremely useful in the treatment of Parkinsonism. When administered to warm-blooded animals (e.g., humans), superior therapeutic blood levels of L-DOPA are observed over that normally observed with conventional enteric coated formulations.