The acute effects of a loading dose of phenylalanine in unipolar depressed patients with and without tardive dyskinesia.
The effects of a loading dose of 100 mg/kg phenylalanine (PHE) were assessed in three groups of DSM-III-R diagnosed unipolar depressed patients: patients with tardive dyskinesia (TD) (n = 11); patients exposed to neuroleptics (NLs) but without TD (n = 10); and patients never exposed to NLs (n = 10). No significant differences were obtained in fasting and 2 hour postloading PHE plasma levels between the groups. A statistically significant correlation was found between Abnormal Involuntary Movements Scale total scores and postloading PHE plasma levels (p less than .05). Three TD patients showed unusually large increases in PHE plasma levels and PHE:large neutral amino acid ratios. Abnormalities in PHE metabolism may contribute to the development and severity of TD in some NL-treated unipolar depressed patients.
Gardos
G
G
Psychopharmacology Program, McLean Hospital, Belmont, Massachusetts 02178.
Cole
J O
JO
Matthews
J D
JD
Nierenberg
A A
AA
Dugan
S J
SJ
D000293:Adolescent; D000328:Adult; D000339:Affect / Q000187:drug effects; D000596:Amino Acids / Q000097:blood; D014150:Antipsychotic Agents / Q000009:adverse effects; D003866:Depressive Disorder / Q000150:complications / Q000188:drug therapy* / Q000523:psychology; D004409:Dyskinesia, Drug-Induced / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010649:Phenylalanine / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use
D000596:Amino Acids; D014150:Antipsychotic Agents; D010649:Phenylalanine