Plasma Alpha-One Acid Glycoprotein and Haloperidol Concentrations in Schizophrenic Patients

Abstract

Thirty six schizophrenic patients were randomly assigned to placebo or haloperidol treatment for 6 weeks. Blood samples to measure plasma alpha-one acid glycoprotein (AAG), haloperidol and reduced haloperidol concentrations were obtained at baseline and weeks 2, 4, and 6. Blood samples were obtained 10-12 h after the evening dose and prior to the morning dose. Haloperidol and reduced haloperidol was assayed by HPLC with electrochemical detection. Plasma AAG levels were assayed by radial immunodiffusion. Patients were clinically assessed by the Brief Psychiatric Rating Scale (BPRS) and Abnormal Involuntary Movement Scale at baseline and weeks 2, 4, and 6. BPRS scores did not significantly decrease during placebo treatment, although a slight drop in plasma AAG levels was found. Haloperidol produced a significant decrease in BPRS scores and plasma AAG levels. Mean plasma haloperidol levels were 12.9 ± 14.7 ng/ml at week 6. Significant correlations between decreasing BPRS scores and plasma AAG levels were not found with only a strong trend at week 2 (r = 0.445, p = 0.073). The role of AAG and psychotropic drug disposition in psychiatric patients requires further evaluation.

Haloperidol moderately inhibits cardiovascular L-type calcium current

“…It is quite often used in the management of numerous behavioural problems in patients after general anaesthesia. Drug concentrations commonly found in the plasma of schizophrenia patients range between 10 and 100 nmol/l ( Javaid et al 1996;Jann et al 1997;Ulrich et al 1998). Study of Kornhuber et al (1999) showed that haloperidol is accumulated in the brain of patients even in higher concentration, approx.…”

“…Concentrations commonly found in the plasma of treated patients vary between 10 and 200 nmol/l (Javaid et al 1996;Jann et al 1997;Ulrich et al 1998;Kornhuber et al 1999). Repeated high doses applied in early postoperative phase in agitated patients after general anesthesia may lead to peak plasma concentration of haloperidol in micromolar range.…”

Simultaneous analysis of haloperidol, its three metabolites and two other butyrophenone‐type neuroleptics by high performance liquid chromatography with dual ultraviolet detection

“…They can vary extensively, depending on disease state. In psychiatric illnesses, especially schizophrenic patients, AAG plasma levels have been reported to be elevated (about 150 mg/dL; Jann et al, 1997). Therefore, the binding study of the drugs to melanin, HSA and AAG is very important.…”