Chemical Properties
Crystalline Solid
Originator
Tiberal,Roche,W. Germany ,1977
Uses
Ornidazole is a drug that cures some protozoan infections. It has been investigated for use in Crohn's disease after bowel resection. It is indicated in treatment of mixed amoebiasis, mixed amoebic dysentery, mixed giardiasis, trichomoniasis, bacterial vaginosis, Sexually transmitted diseases, infections of gynaecology, lower respiratory tract infections, ENT, surgical and dental infections.
Definition
ChEBI: A C-nitro compound that is 5-nitroimidazole in which the hydrogens at positions 1 and 2 are replaced by 3-chloro-2-hydroxypropyl and methyl groups, respectively. It is used in the treatment of susceptible protozoal infections and for the
treatment of anaerobic bacterial infections.
Manufacturing Process
5g of 1-(2,3-epoxypropyl)-2-methyl-5-nitroimidazole was added to 30 ml of concentrated aqueous hydrochloric acid. The solution was heated to the boiling point for 20 minutes, chilled, diluted with 30 ml of water and carefully neutralized with ammonia to a pH of 7 to 8. It was then saturated with ammonium sulfate. The precipitated oil crystallized after several days. Recrystallized from toluene, there was obtained the 1-(3-chloro-2hydroxypropyl)-2-methyl-5-nitroimidazole product melting at 77°C to 78°C.
Therapeutic Function
Antiinfective
Pharmaceutical Applications
A 5-nitroimidazole available for oral administration, intravenous infusion and as a vaginal pessary. Its activity closely parallels that of metronidazole and tinidazole.
Peak plasma levels after a single 750 mg or 1.5 g oral dose reach 11 mg/L and 30 mg/L, respectively, within about 2 h. The half-life is 12–14 h. It is well absorbed from the vagina, with peak plasma concentrations of 5 mg/L being reached 12 h after the insertion of a 500 mg vaginal pessary. After a single 1 g intravenous infusion for colorectal surgery, serum levels reached about 24 mg/L after 15 min and about 6 mg/L after 24 h. It has wide tissue distribution, including CSF. Plasma protein binding is 10–15%.
It is metabolized in the liver, mainly to hydroxymethyl derivatives. The plasma clearance rate decreases in hepatic failure because of reduced liver metabolism and decreased biliary elimination. About 60% of an oral dose is recovered in the urine and 20% in the feces. The dosing interval should be doubled in patients with severe hepatic impairment, but it is unnecessary to reduce the dose in patients with impaired renal function. It is removed by hemodialysis.
Toxicity and side effects are similar to those of metronidazole and tinidazole and it has similar clinical uses. It has been shown to be effective for the prevention of recurrence of Crohn’s disease after ileocolonic resection.
Safety Profile
Poison by intravenous route. Moderately toxic by ingestion and intraperitoneal routes. Experimental reproductive effects. Mutation data reported. Whenheated to decomposition it emits very toxic fumes of Clí and NOx.
