Synthetic antibacterial anti-tuberculosis drug. It has strong activity against bacteria in the growth and reproduction stage, and has almost no effect on bacteria in the dormant stage. It has high antibacterial activity against various types of mycobacteria. There is no cross-resistance between Mycobacterium tuberculosis and other drugs. It may inhibit the metabolism of sensitive bacteria, inhibit RNA synthesis, and interfere with the protein metabolism of Mycobacterium tuberculosis, thereby causing bacterial death. In large doses, it can cause cleft palate, brain exposure, and spinal deformity in mouse experiments; it can cause mild cervical deformity in rat experiments; it can cause cyclops, short limbs, and cleft palate in rabbit experiments.

This product is a dried yeast body, rich in B vitamins, and has an auxiliary therapeutic effect on indigestion.

This product is a prodrug of acyclovir. It is rapidly absorbed after oral administration and quickly converted into acyclovir in the body. Its antiviral effect is exerted by acyclovir. After acyclovir enters the herpes infected cells, it competes with deoxynucleoside for viral thymidine kinase or cellular kinase. The drug is phosphorylated into activated acyclosine triphosphate, which competes with deoxyguanine triphosphate for viral DNA polymerase as a substrate for viral replication, thereby inhibiting viral DNA synthesis and showing antiviral effect. The antiviral activity of this product in vivo is better than that of acyclovir, and the therapeutic index for herpes simplex virus type I and type II is 42.91% and 30.13% higher than that of acyclovir, respectively. It also has a high efficacy against varicella zoster virus and has very low toxicity to mammalian host cells.

Macrolide antibiotics have inhibitory effects on Gram-positive bacteria such as Staphylococcus aureus, Streptococcus, and Pneumococcus, as well as some Gram-negative bacteria such as Haemophilus influenzae, Bordetella pertussis, Neisseria gonorrhoeae, Legionella pneumophila, and some anaerobic bacteria such as Bacteroides fragilis, Streptococcus peptostreptococcus, and Propionibacterium acnes. In addition, they also have inhibitory effects on mycoplasmas. In vivo, the antibacterial activity against some bacteria such as Staphylococcus aureus, Streptococcus, and Haemophilus influenzae is stronger than that of erythromycin. The antibacterial effect is produced by hindering the association of the 50S subunit of the nucleoprotein and inhibiting protein synthesis.

It has a direct relaxant effect on the smooth muscles of the respiratory tract, partly by inhibiting phosphodiesterase to increase the intracellular cAMP content, and partly as a result of the release of endogenous adrenaline and norepinephrine; as a purine receptor blocker, it can counteract the contractile effect of adenine and other substances on the respiratory tract, enhance the contractility of the diaphragm and thus improve respiratory function.