Cephalexin is a first-generation cephalosporin with an antibacterial spectrum similar to that of cephalothin, but its antibacterial activity is poorer than that of the latter. Except for Enterococcus and methicillin-resistant Staphylococci, most strains of Streptococcus pneumoniae, hemolytic Streptococcus, and Staphylococcus aureus that produces or does not produce penicillinase are sensitive to this product. This product has a good antibacterial effect on Neisseria, but Haemophilus influenzae is less sensitive to this product; this product 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.

It binds to the 50s ribosome subunit of sensitive microorganisms and interferes with their protein synthesis (without affecting nucleic acid synthesis). It is effective against a variety of pathogens, including Gram-positive aerobic microorganisms, Gram-negative aerobic microorganisms, anaerobic bacteria, sexually transmitted disease microorganisms and other microorganisms.

It can inhibit the synthesis of prostaglandins and has antipyretic and analgesic effects

Can resist subtype I influenza virus and inhibit virus reproduction

It is an anti-allergic drug that can relieve symptoms such as runny nose, nasal congestion, and sneezing.

It has antipyretic and sedative effects

It is a central nervous system stimulant that can enhance the antipyretic and analgesic effects of acetaminophen and reduce central nervous system inhibitory effects such as drowsiness and dizziness caused by other drugs.

It is a glycoside of dehydrogenated flavonoids, which often coexists with vitamin C in food. It may participate in the action of oxidoreductase in the body, affect the activity of the thyroid gland, and protect adrenaline from oxidation. It can enhance the action of vitamin C and promote its accumulation in the body, maintain vascular elasticity, enhance capillary resistance, reduce its fragility and permeability, and promote its cell proliferation and prevent blood cell aggregation. It also has anti-inflammatory and anti-allergic effects.

It has a certain antibacterial effect on most Gram-positive and Gram-negative bacteria, and inhibits the early synthesis of bacterial cell walls, thereby blocking the synthesis of bacterial cell walls and causing their death.