Pharmacological properties
Pharmacodynamics. Ornigil is a derivative of 5-nitroimidazole antibiotic, has an antibacterial effect similar to the action of metronidazole and other 5-nitroimidazoles.
Effective against Trichomonas vaginalis, Entamoeba histolytica, Giardia lamblia (Giardia intestinalis), as well as some anaerobic bacteria such as Gardnerella vaginalis, Bacteroides and Clostridium spp., Fusobacterium and anaerobic cocci. Has antiprotozoal activity against Balantidium coli, Blastocystis hominis, Trichomonas vaginalis, Trichomonas foetus, Giardia intestinalis and Entamoeba histolytica.
By mechanism of action, Ornigil is a DNA-tropic drug with selective activity against microorganisms that have enzyme systems capable of reducing the nitro group and catalyzing the interaction of ferridoxine group proteins with nitro compounds. After penetration of the drug into the microbial cell, the mechanism of its action is due to the reduction of the nitro group under the influence of nitroreductases of the microorganism and the activity of the already reduced nitroimidazole. The reduction products form complexes with DNA, causing its degradation, disrupting the processes of DNA replication and transcription. In addition, the products of the drug's metabolism have cytotoxic properties and inhibit the processes of cellular respiration.
Pharmacokinetics. With intravenous drip administration at an initial dose of 15 mg / h and subsequent administration at a dose of 7.5 mg / kg of body weight every 6 hours, the equilibrium C max is 26 μg / ml, and the minimum is 18 μg / ml. Ornidazole is distributed in many tissues and biological fluids of the body, such as bile, saliva, pleural, peritoneal fluids and cerebrospinal fluid (about 43% of the concentration in blood plasma), vaginal secretion, bone tissue, liver, erythrocytes. Binding to blood plasma proteins is 20%. Ornidazole penetrates the placental barrier, is excreted in breast milk. About 30-60% of the drug is metabolized in the body by hydroxylation, oxidation and glucuronidation. The main metabolite (2-oxymetronidazole) also has antiprotozoal and antibacterial effects. Ornidazole is excreted mainly in the urine (60-80%), partially in the bile in unchanged form and in the form of metabolites within 5 days after a single administration.
Indication
Parenteral administration of the drug is indicated in cases of acute and severe infection or when oral administration is not possible in the following diseases and conditions:
anaerobic systemic infections caused by ornidazole-sensitive microflora: septicemia, meningitis, peritonitis, postoperative wound infections, postpartum sepsis, septic abortion and endometritis; prevention of infections caused by anaerobic bacteria during surgical interventions (especially during operations on the colon and rectum), during gynecological operations; amoebic dysentery with severe course, all extraintestinal forms of amebiasis, giardiasis, liver abscess.
Application
The drug is administered intravenously over 15-30 minutes.
For anaerobic infections, adults and children over 12 years of age are prescribed an initial dose of 500-1000 mg, then 500 mg every 12 hours or 1000 mg every 24 hours for 5-10 days (stepwise dose). After stabilization of the patient's condition, oral ornidazole should be switched to (for example, 500 mg tablets, 1 tablet every 12 hours).
Children under 12 years of age with a body weight of 6 kg are prescribed a daily dose of 20 mg/kg of body weight, divided into 2 doses, for 5-10 days.
For the prevention of anaerobic infections in adults and children over 12 years of age, Ornigil is administered intravenously at a dose of 500-1000 mg half an hour before surgery.
For the prevention of mixed infections, Ornigil should be used in combination with aminoglycosides, penicillin or cephalosporins. The drugs must be administered separately.
Severe amoebic dysentery, all extraintestinal forms of amebiasis. For adults and children over 12 years of age, the first dose is 500-1000 mg, then 500 mg every 12 hours for 3-6 days.
Children under 12 years of age are given Ornigil at a dose of 20-30 mg/kg of body weight, divided into 2 doses.
In case of impaired renal function, the interval between administrations is increased or the single and daily dose of the drug is reduced.
Contraindication
Hypersensitivity to the components of the drug; organic diseases of the central nervous system; epilepsy, multiple sclerosis; circulatory disorders; chronic alcoholism; I trimester of pregnancy and breastfeeding; body weight 6 kg.
Side effects
Gastrointestinal: metallic taste, dry mouth, tongue coating, nausea, loss of appetite, abdominal pain, diarrhea, vomiting, changes in liver function tests.
Nervous system: headache, dizziness, tremor, muscle rigidity, impaired coordination of movements, ataxia, convulsions, confusion, signs of sensory or mixed peripheral neuropathy.
Allergic reactions: very rarely - angioedema; skin rash, itching, urticaria.
Others: moderate leukopenia, darkening of urine color, cardiovascular disorders.
Special instructions
Use with caution in patients with liver failure (dose should be reduced), patients with brain damage, hematopoiesis disorders (high risk of leukopenia, neutropenia); patients who abuse alcohol.
Incompatibility. The solution is not mixed with other medicines.
Use during pregnancy and breastfeeding. Ornigil is contraindicated in the first trimester of pregnancy. In the second and third trimesters, the drug is prescribed only for absolute indications.
Children. There are no data on contraindications for taking the drug in children under 1 year of age, if the child's body weight is at least 6 kg.
The ability to influence the reaction speed when driving vehicles or working with other mechanisms. Ornigil reduces the ability to concentrate and the reaction speed.
The possibility of such manifestations must be considered for patients who drive vehicles or work with other mechanisms.
Interactions
Ornidazole potentiates the action of oral coumarin anticoagulants, which requires appropriate correction of their dose. Ornidazole increases the period of muscle relaxant action of vancuronium.
The concentration of the drug decreases with simultaneous use with inducers of microsomal enzymes (phenobarbital, rifampicin) and increases with simultaneous use with inhibitors of liver microsomal systems, in particular with H2-receptor blockers (cimetidine).
When used with other 5-nitroimidazole derivatives, isolated cases of peripheral neuritis, mental depression, and epileptiform seizures have been reported.
Overdose
Symptoms: loss of consciousness, headache, dizziness, tremors, seizures, depression, peripheral neuritis, nausea, vomiting.
Treatment: symptomatic, specific antidote unknown.
Storage conditions
Store in a place protected from light at a temperature not exceeding 25 ° C. Do not freeze.
