If you've seen the movie "Awakenings," or read the book by Oliver Sacks, you've witnessed the wonder of the wonder drug L-dopa --and the horror. Dramatically awakened by it from a long Parkinsonian slumber, Robert De Niro's character soon awakens too much. He becomes a grotesquely twitching, jerking ball of tics -- a man who looks very much like someone in whom dopamine, the neurotransmitter made from L-dopa which slowly vanishes in the course of Parkinson's disease (PD), has gained the upper hand over another major movement-regulating neurotransmitter: serotonin. Indeed, he looks like someone who could benefit from another precursor that neurologists across the ocean were beginning to use, back then in the 1960's, to sedate the erratic muscle jerks -- the myoclonus -- of a different group of patients: 5-HTP.

Not just the florid symptoms of dopamine excess (which include paranoia and visual hallucinations), but also the sluggishness of dopamine deficiency, the depression that afflicts 50 percent of PD sufferers, and the on/off alternations between these extremes have all been attributed, in part, to a related deficiency, common in PD, of serotonin. Some researchers have taken the obvious clinical leap. Their studies, which have yielded wildly mixed results, suggest that while serotonin boosting sometimes worsens PD by upsetting the delicate balance between dopamine and serotonin even more, at other times it is a godsend. For one lucky patient, a low 100 mg/day dose of 5-HTP, with adjunctive carbidopa (a drug often prescribed to minimize the conversion of 5-HTP to serotonin before it reaches the brain), resolved her severe, untreatable depression and markedly improved her PD for at least two years. Each of three times she was switched to a placebo she promptly relapsed (Klein et al., 1986).

Books Popular Music Classical Music Videos Search by keywords:

Toys Consumer Electronics Search by keywords:

• Klein, P., et al., "Consequences of Chronic 5-Hydroxy-Tryptophan in Parkinsonian Instability of Gait and Balance and in Other Neurological Disorders," Advances in Neurology, 45 (1986): 603-4.