This product is a selective 5-HT3 receptor antagonist. Its mechanism of action may be to antagonize the 5-HT3 receptors in the peripheral vagus nerve endings and central chemoreceptor areas, thereby blocking the vomiting reflex caused by factors such as chemotherapy and surgery that promote the release of 5-HT from intestinal chromaffin cells and excite the vagus afferent nerves. This product has high selectivity and no side effects such as extrapyramidal reactions and excessive sedation.

This product is a phenothiazine antipsychotic, and its mechanism of action is mainly related to its blocking of dopamine receptors (DA2) in the mesolimbic system and mesocortical pathways. It has a blocking effect on dopamine (DA1) receptors, 5-hydroxytryptamine receptors, M-type acetylcholine receptors, and α-adrenaline receptors, and has a wide range of effects. In addition, this product can inhibit the dopamine receptors in the medulla oblongata emetic chemoreceptor area at low doses, and directly inhibit the vomiting center at high doses, producing a strong antiemetic effect. It inhibits the body temperature regulation center and lowers the body temperature. The body temperature can change with changes in the external environment. It blocks the action of peripheral α-adrenaline receptors, dilates blood vessels, causes a drop in blood pressure, and also has a certain effect on the endocrine system.

It is an oxidized derivative of adrenaline and has no adrenaline-mimetic effect, so it does not affect blood pressure and heart rate, but it can enhance the resistance of capillaries to damage, stabilize the acidic mucopolysaccharides in blood vessels and surrounding tissues, reduce the permeability of capillaries, and enhance the retraction effect of damaged capillary ends, making it difficult for blood clots to fall off the tube wall, thereby shortening the hemostasis time, but it does not affect the coagulation process.

As a histamine H1 receptor antagonist, it can counteract the capillary dilation caused by allergic reactions, reduce the permeability of capillaries, and relieve wheezing caused by bronchial smooth muscle contraction. It has a long-lasting antihistamine effect and also has a significant central inhibitory effect, which can increase the effects of anesthetics, analgesics, hypnotics and local anesthetics. This product is mainly metabolized in the liver.

Antiviral drug. It has the effect of inhibiting the growth of many viruses such as respiratory syncytial virus, influenza virus, hepatitis A virus, adenovirus, etc. in vitro, and its mechanism is not fully understood. This product does not change the adsorption, invasion and uncoating of viruses, nor does it induce the production of interferon. After entering the virus-infected cells, the drug is rapidly phosphorylated, and its product acts as a competitive inhibitor of viral synthase, inhibiting inosine monophosphate dehydrogenase, influenza virus RNA polymerase and mRNA guanosine transferase, thereby causing a decrease in intracellular guanosine triphosphate, impairing viral RNA and protein synthesis, and inhibiting viral replication and transmission. It may also have an immune effect and neutralizing antibody effect on respiratory syncytial virus.