1. Nifedipine is a dihydropyridine calcium antagonist that can selectively inhibit the transmembrane transport of calcium ions into myocardial cells and smooth muscle cells, and inhibit the release of calcium ions from intracellular reservoirs without changing the plasma calcium ion concentration. 2. It can simultaneously relax the coronary arteries in the normal blood supply area and the ischemic area, antagonize spontaneous or ergonovine-induced coronary artery spasm, increase the delivery of myocardial oxygen to patients with coronary artery spasm, and relieve and prevent coronary artery spasm. It can also inhibit myocardial contraction, reduce myocardial metabolism, and reduce myocardial oxygen consumption. On the other hand, it can relax peripheral resistance vessels, reduce peripheral resistance, reduce systolic and diastolic blood pressure, and reduce cardiac afterload. 3. It can delay the sinoatrial node function and atrioventricular conduction of isolated hearts. Electrophysiological studies of whole animals and humans have not found that this product has the effect of delaying atrioventricular conduction, prolonging the recovery time of the sinoatrial node, and slowing down the sinoatrial node rate.

Cephalexin is a first-generation cephalosporin. It is sensitive to most strains of Streptococcus pneumoniae, hemolytic Streptococcus, and Staphylococcus aureus that produces or does not produce penicillinase. It has a good antibacterial effect on Neisseria and has a certain antibacterial effect on some Escherichia coli, Proteus mirabilis, Salmonella and Shigella. The remaining Enterobacteriaceae, Acinetobacter, Pseudomonas aeruginosa, and Bacteroides fragilis are resistant to this product. Fusobacterium and Veillonella are generally sensitive to this product, and anaerobic Gram-positive cocci are moderately sensitive to this product. The oral median lethal dose for mice is 2600 mg/kg.

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.

This product is an anticholinergic drug that can significantly relieve gastrointestinal smooth muscle spasm.

This product is a first-generation cephalosporin, which has good antibacterial effect on some strains of Gram-positive cocci such as non-penicillinase-producing and penicillinase-producing Staphylococcus aureus, coagulase-negative Staphylococci, group A hemolytic Streptococcus, Streptococcus pneumoniae and viridans Streptococcus. Anaerobic Gram-positive bacteria are mostly sensitive to this product, while Bacteroides fragilis is resistant to it. Methicillin-resistant Staphylococci and Enterococci are resistant to this product. The effect of this product on Gram-positive and Gram-negative bacteria is similar to that of cephalexin. This product has a certain effect on Neisseria gonorrhoeae, and is also active against enzyme-producing Neisseria gonorrhoeae; its activity against Haemophilus influenzae is poor. The mechanism of action is the same as other cephalosporins, which is to inhibit the synthesis of bacterial cell walls.