Ranitidine (bismuth citrate)

Ranitidine bismuth citrate is a potent, selective and orally active histamine H2-receptor antagonist that inhibits gastric secretion. Ranitidine bismuth citrate antagonizes Histamine (HY-B1204)-induced increases of the guinea-pig isolated rat atrium and Histamine-induced relaxations of the rat isolated uterine horn, with pA₂ values of 7.2 and 6.95, respectively. Ranitidine bismuth citrate has selectivity for SARS-CoV-2-infected cells. Ranitidine bismuth citrate also has anti-Helicobacter pylori infection. Ranitidine bismuth citrate inhibits breast tumor development and spread in mice^[1][2][3][4]. IC50 & Target:IC50: 3.3 μM^[1] In Vitro:Ranitidine bismuth citrate (0.1-1 μM, 5 min) is a potent irreversible inhibitor of both the ATPase (IC₅₀ = 0.69 μM, K_i = 0.97 μM ) and DNA-unwinding (IC₅₀ = 0.74 μM, K_i = 0.39 μM) of the SARS-CoV-2 helicase^[2].
Ranitidine bismuth citrate (24 hours) shows potent activity against SARS-CoV-2 with an EC₅₀ value of 2.3 μM in Vero E6 cells^[2].
In Vivo:Ranitidine (0.03-3 mg/kg; i.v.; once) bismuth citrate inhibits Histamine (HY-B1204)- and Pentagastrin (HY-A0261)-induced gastric acid secretion in the perfused stomach preparation of the anaesthetized rat^[1].
Ranitidine bismuth citrate (150 mg/kg; i.p.; once daily; 4 days) suppresses SARS-CoV-2 replication, and relieves virus-associated pneumonia in a golden Syrian hamster model^[2].
In the rat, Ranitidine bismuth citrate (3-30 mg/kg p.o.) prevents gastric mucosal damage induced by ethanol (fundic damage) and indomethacin (antral damage)^[3].
In ferrets naturally colonized with H. mustelae, Ranitidine bismuth citrate (po; 12-24 mg/kg; twice daily; for 4 weeks) causes a dose related clearance of H. mustelae^[3].
Ranitidine (8 mg/kg; oral administration; administered every other day; treatment for 8 days) bismuth citrate reduces the number of CD11b⁺Ly6C^hi cells in the spleen and bone marrow of BALB/c mice^[4].
Ranitidine (8 mg/kg; oral administration; administered every other day; treatment for 8 days) bismuth citrate inhibits lung metastasis in BALB/c mice bearing 4T1 breast cancer^[4].
Ranitidine (8 mg/kg; oral administration; administered every other day; for 14 days) bismuth citrate inhibits primary tumor growth in the E0771 breast cancer model of C57BL/6 mice^[4].
Ranitidine (dose enabling mice to ingest 6-8 mg/kg per day; added to drinking water; changed every 3 days; treatment starting from weaning (~4 weeks) until the end of the experiment (23-26 weeks))bismuth citrate increases the latency of breast tumorigenesis and reduces the number of tumors in LKB1^-/-NIC mice^[4].