| Indication | Used in the treatment of schizophrenia, organic brain disorders, alcoholism and psychoneuroses. |
| Pharmacodynamics | Mesoridazine, the besylate salt of a metabolite of thioridazine, is a phenothiazine tranquilizer. Pharmacological studies in laboratory animals have established that mesoridazine has a spectrum of pharmacodynamic actions typical of a major tranquilizer. In common with other tranquilizers it inhibits spontaneous motor activity in mice, prolongs thiopental and hexobarbital sleeping time in mice and produces spindles and block of arousal reaction in the EEG of rabbits. It is effective in blocking spinal reflexes in the cut and antagonizes d-amphetamine excitation and toxicity in grouped mice. It shows a moderate adrenergic blocking activity in vitro and in vivo and antagonizes 5-hydroxytryptamine in vivo. Intravenously administered, it lowers the blood pressure of anesthetized dogs. It has a weak antiacetylcholine effect in vitro. |
| Mechanism of action | Based upon animal studies, mesoridazine, as with other phenothiazines, acts indirectly on reticular formation, whereby neuronal activity into reticular formation is reduced without affecting its intrinsic ability to activate the cerebral cortex. In addition, the phenothiazines exhibit at least part of their activities through depression of hypothalamic centers. Neurochemically, the phenothiazines are thought to exert their effects by a central adrenergic blocking action. |
| Absorption | Well absorbed from the gastrointestinal tract. |
| Volume of distribution | Not Available |
| Protein binding | 4% |
| Metabolism | Not Available |
| Route of elimination | Not Available |
| Half life | 24 to 48 hours |
| Clearance | Not Available |
| Toxicity | Oral LD50 is 560 ± 62.5 mg/kg and 644 ± 48 mg/kg in mouse and rat, respectively. Symptoms of overdose may include emesis, muscle tremors, decreased food intake and death associated with aspiration of oral-gastric contents into the respiratory system. |