Chlorpromazine and lithium interaction: a biochemical and histological study

Area of Science:

• Pharmacology and Toxicology
• Biochemistry
• Histopathology

Background:

• Lithium chloride (LiCl) and chlorpromazine (CPZ) are commonly administered drugs.
• Understanding their individual and combined effects is crucial for patient safety.
• Previous research indicates potential for adverse reactions with concurrent use.

Purpose of the Study:

• To investigate the biochemical and histological effects of LiCl and CPZ, alone and in combination.
• To evaluate potential drug-drug interactions between LiCl and CPZ.
• To assess the impact on hepatic enzymes and corneal tissue in a mouse model.

Main Methods:

• Female C57BL/6J mice were divided into four groups: saline control, LiCl, CPZ, and combined LiCl + CPZ.
• Drugs were administered daily for 8 consecutive days via intraperitoneal injection (CPZ) or as drinking fluid (LiCl).
• Biochemical assays measured hepatic liver alcohol dehydrogenase and mitochondrial liver aldehyde dehydrogenase activity.
• Histological examination assessed corneal cellularity, mitotic activity, and inflammation.

Main Results:

• Combined LiCl and CPZ treatment induced hepatic liver alcohol dehydrogenase.
• LiCl inhibited mitochondrial liver aldehyde dehydrogenase; this effect was antagonized by co-administration of CPZ.
• CPZ treatment alone caused corneal cellularity and mitotic figures without inflammation.
• LiCl treatment resulted in variations in corneal cell size, shape, pigmentation, nuclear aggregation, and inflammation.
• Combined LiCl and CPZ treatment showed similar corneal alterations to LiCl alone, but with mitotic figures above the basal cell layer, indicating enhanced corneal toxicity.

Conclusions:

• A significant drug-drug interaction exists between LiCl and CPZ.
• Combined administration potentiates corneal toxicity compared to individual treatments.
• These findings may explain adverse reactions observed in patients receiving concurrent LiCl and CPZ therapy.