¹⁹F‐magnetic resonance spectroscopy and chemical shift imaging for schizophrenic patients using haloperidol decanoate

Abstract

Haloperidol decanoate is widely used in the maintenance treatment of schizophrenia and other psychotic disorders, but knowledge concerning its pharmacokinetics at the injected region is very limited. Because the chemical structure of haloperidol contains fluorine, in vivo 19F-magnetic resonance (MR) spectroscopy (repetition time (TR) = 1 s) and chemical shift imaging (CSI; TR = 1 s, pixel size = 15 x 15 mm) were performed in schizophrenic patients who were treated with haloperidol decanoate (three men and one woman) to measure its diachronic change at the injection point and visualize its local distribution after intramuscular injection. 19F signals (T1 time = 365 ms) were obtained at the haloperidol decanoate-injected region. The decrease rate of the signal-to-noise ratio (SNR) by 19F-MR spectroscopy seemed large in comparison with that of the plasma haloperidol concentration. The distribution was clearly visualized by 19F-CSI for a few days after the injection, but after 1 week could no longer be seen. Although the slow-release characteristics of depot neuroleptics have been explained by the slow diffusion of esterified neuroleptics from the oil vehicle, this result may suggest that there are other mechanisms involved in maintaining the plasma haloperidol concentration. In vivo 19F-MR spectroscopy and CSI are potentially applicable for the pharmacokinetic analysis of haloperidol and other drugs containing fluorine in their structure.

Multiparametric magnetic resonance imaging to characterize cabotegravir long‐acting formulation depot kinetics in healthy adult volunteers

“…Noninvasive imaging approaches to assess LA drug distribution in humans for durations of weeks to months have been sparingly applied, because detection techniques to directly assess drug substance are not readily available 29–33 . Computed tomography has been used to assess LA injectable depot location variability between gluteal muscle and SC adipose fat and, in doing so, has been used to determine the association between BMI and IM misinjections 28,34 .…”

Black Tea Source, Production, and Consumption: Assessment of Health Risks of Fluoride Intake in New Zealand

“…Typical fluoridated medications that have been found to contribute to fluoride burden include fluoroquinolone antibiotics [82]; the antifungal medication voriconazole [83]; the antimetabolite drug fluorouracil [84]; the antiarrhythmic drug flecainide [85]; anti-inflammatory drugs diclofenac, niflumic acid, flufenamic, and antrafenine [86, 87]; the antimalarial drug 5-fluoro-amodiaquine [88]; antipsychotic medications such as haloperidol [89]. There is evidence to suggest that Teflon products may significantly alter the F uptake in prepared foods [90].…”

Clinical Perspectives of Hybrid Proton-Fluorine Magnetic Resonance Imaging and Spectroscopy

“…The drug's fluorine signal could be measured with fluorine spectroscopy for at least 16 days, which was not possible with radioactive tracers. 57 Therapy monitoring with radioactive tracers provides high sensitivity; however, imaging time is limited because of the decay of the isotope, and it causes radioactive exposure to the patient.…”