Quinine is a quinoline derivative that can bind to the DNA of malarial parasites to form a complex that inhibits DNA replication and RNA transcription, thereby inhibiting the protein synthesis of the parasites. In addition, quinine can reduce the oxygen consumption of malarial parasites, resist the phosphorylase in malarial parasites and interfere with their sugar metabolism. Quinine also causes hemochromatin aggregation, but it develops slowly, rarely forms large clumps, and is often accompanied by cell death. In the blood, a certain concentration of quinine can cause premature rupture of parasitized red blood cells, thereby preventing the maturation of schizonts. This product is ineffective in the irritated stage, and a long course of treatment can cure malignant malaria, but it has no direct effect on the gametocytes of malignant malaria, so it cannot interrupt transmission.

This product is an acid-resistant and penicillinase-resistant penicillin. It has good antibacterial activity against penicillinase-producing Staphylococci, but its antibacterial activity against various streptococci and non-penicillinase-producing Staphylococci is inferior to penicillin G. It exerts its bactericidal effect by inhibiting bacterial cell wall synthesis.

It has a direct relaxant effect on the smooth muscles of the respiratory tract; it increases the intracellular cAMP content partly by inhibiting phosphodiesterase; it produces a bronchodilator effect partly by releasing endogenous adrenaline and norepinephrine; it acts as a purine receptor blocker to counteract the contractile effect of adenine and other substances on the respiratory tract; it enhances the contractility of the diaphragm and improves respiratory function.

Unspecified