MIC: 10-100 μg/mL in most of the strains

Flupenthixol, introduced in 1965 by Lundbeck, marketed under brand names such asDepixol.Flupenthixolis atypical antipsychoticdrugof thethioxantheneclass. In addition to single drug preparations, flupenthixol is also available asflupentixol/melitracen, which is acombination product.

In vitro: The minimum inhibitory concentration of flupenthixol was determined by the National Committee for Clinical Laboratory Standards agar dilution method. MICs ranged from 10–100 μg/mL for most of the strains, whilst some strains were inhibited at even lower concentrations. The mode of action of flupenthixol was found to be bacteriostatic against Staphylococcus aureus and Vibrio cholerae [1].

In vivo: In the in vivo experiments, flupenthixol was able to contribute significant protection to a Swiss strain of white mice challenged with 50 median lethal dose of a mouse-virulent strain at a drug concentration of 15 μg/mouse. Moreover, flupenthixol reduced remarkably the number of viable bacteria in organs and blood of mice treated with flupenthixol [1].

Clinical trial: An clinical trial was carried out to evaluate the effectiveness and side-effects of flupenthixol treatment. The results showed that symptoms of depression, worrying, withdrawal, as well as psychomotor retardation were improved significantly with flupenthixol. Thus, it was concluded that schizophrenic patients characterized by depressive symptoms might more benefit to the flupenthixol treatment [2].

References:
[1] Jeyaseeli L,Gupta AD,Asok Kumar K,Mazumdar K,Dutta NK,Dastidar SG.  Antimicrobial potentiality of the thioxanthene flupenthixol through extensive in vitro and in vivo experiments. Int J Antimicrob Agents.2006 Jan;27(1):58-62.
[2] Kong DS,Yeo SH.  An open clinical trial with the long-acting neuroleptics flupenthixol decanoate and fluphenazine decanoate in the maintenance treatment of schizophrenia. Pharmatherapeutica.1989;5(6):371-9.