Metronidazole Tablets 0.2g

Metronidazole Tablets. The indications are for the treatment of intestinal and extra-intestinal amoebiasis (such as amoebic liver abscess, pleural amoebiasis, etc.). It can also be used for the treatment of trichomoniasis vaginalis, balantidiasis, cutaneous leishmaniasis, Dracunculus medinensis infection, etc. Currently, it is also widely used for the treatment of anaerobic bacterial infections.

【Drug Name】

Generic name: Metronidazole Tablets

English name: Metronidazole Tablets

【Ingredients】Metronidazole

Chemical name: 2-methyl-5-nitro-imidazol-1-ethanol

Molecular formula: C₆H₉N₃O₃

Molecular weight: 171.16

【Appearance】A white or off white tablet.

【Specification】0.2 g.

【Indications】Used for treating intestinal and extraintestinal amoebic diseases (such as amoebic liver abscess, pleural amoebic disease, etc.). It can also be used to treat vaginal trichomoniasis, small bag worm disease, skin leishmaniasis, and nematode infection. Currently, it is widely used for the treatment of anaerobic bacterial infections.

【Usage and dosage】

1. Common usage for adults

① Intestinal amoebiasis, 0.4-0.6g (2-3 tablets) once, 3 times a day, with a treatment course of 7 days; Extraintestinal amoebiasis, 0.6-0.8g (3-4 tablets) once, 3 times a day, with a treatment course of 20 days.

② Giardia disease, 0.4g (2 tablets) once, 3 times a day, treatment course of 5-10 days.

③ Dracunculiasis , 0.2g (1 tablet) once, 3 times a day, treatment course of 7 days.

④ Small bag worm disease, 0.2g (1 tablet) once, twice a day, with a treatment course of 5 days.

⑤ Cutaneous leishmaniasis, 0.2g (1 tablet) once, 4 times a day, treatment for 10 days. Repeat the treatment course after a 10 day interval.

⑥ Trichomoniasis, 0.2g per dose (1 tablet), 4 times a day, with a treatment course of 7 days; Suppositories can be used simultaneously, with 0.5g inserted into the vagina every night for 7-10 days.

⑦ Anaerobic bacterial infection, orally, take 0.6-1.2g (3-6 tablets) daily, divided into 3 doses, with 7-10 days as one course of treatment.

2. Common dosage for children

① Amoebiasis, administered orally in 3 doses per day at a weight of 35-50mg/kg, with 10 days as one course of treatment.

② Giardia disease, take orally at a dose of 15-25mg/kg per day, divided into 3 doses, for 10 consecutive days; The dosage for treating nematode disease, small bag worm disease, and trichomoniasis is the same as that for treating Giardia.

③ Anaerobic bacterial infection, orally administered at a dose of 20-50mg/kg of body weight per day.

【Adverse reactions】15% to 30% of cases experience adverse reactions, the gastrointestinal reactions being the most common, including nausea, vomiting, loss of appetite, and abdominal cramps, which generally do not affect treatment; Neurological symptoms include headache, dizziness, occasional sensory abnormalities, limb numbness, ataxia, multiple neuropathy, etc. High doses can cause convulsions. A small number of cases may experience urticaria, flushing, itching, cystitis, dysuria, metallic taste in the mouth, and decreased white blood cells, all of which are reversible and self recover after discontinuation of the medicine.

【Contraindication】Prohibited for patients with active central nervous system disorders and hematological disorders.

【Precautions】

(1) Interference with diagnosis: The metabolites of this product can cause urine to appear dark red.

(2) The dosage for patients with pre-existing liver diseases should be reduced. medicine should be discontinued when there is movement disorder or other central nervous system symptoms. Before repeating a course of treatment, a white blood cell count should be performed. For patients with anaerobic bacterial infection combined with renal failure, the dosing interval should be extended from 8 hours to 12 hours.

(3) This product can inhibit alcohol metabolism. During medicine, alcohol should be avoided. Symptoms such as abdominal pain, vomiting, and headache may occur after drinking alcohol.

【Pregnant and lactating women】Pregnant and lactating women are prohibited from using it.

【Children】 Not clear.

【Elderly Patients】Not clear.

【Drug Interactions】This product can enhance the effect of anticoagulant drugs such as warfarin. The combination with oxytetracycline can interfere with the clearance of Trichomonas vaginalis by metronidazole.

【Overdosage】High doses can cause convulsions.

【Pharmacology and toxicology】This product is a nitroimidazole derivative that can inhibit the redox reaction of amoebic protozoa, causing the nitrogen chain of the protozoa to break. In vitro experiments have shown that when the drug concentration is 1-2mg/L, histolytic amoebas can undergo morphological changes within 6-20 hours and are completely killed within 24 hours. When the concentration is 0.2mg/L, histolytic amoebas can be killed within 72 hours. This product has a powerful ability to kill trichomonas, but its mechanism is unclear.

Metronidazole has a bactericidal effect on anaerobic microorganisms, and the metabolites generated during its reduction in the human body also have anti anaerobic effects, inhibiting the synthesis of deoxyribonucleic acid in bacteria, thereby interfering with bacterial growth and reproduction, and ultimately leading to bacterial death.

It has carcinogenic effects on certain animals.

【Pharmacokinetics】 After oral or rectal administration, the drug can be rapidly and completely absorbed with a protein binding rate of [5%]. After absorption, it is widely distributed in various tissues and body fluids, and can pass through the blood-brain barrier. The effective concentration of the drug can appear in saliva, placenta, bile, breast milk, amniotic fluid, semen, urine, pus, and cerebrospinal fluid. It has been reported that the concentration of the drug in placenta, breast milk, and bile is similar to that in blood. The blood drug concentration in cerebrospinal fluid of healthy individuals is 43% of the blood drug concentration during the same period. For a few patients with brain abscess, after taking 1.2-1.8g per day, the drug concentration in pus (34-45mg/L) is higher than that in blood during the same period (11-35mg/L). After ear infection, the drug concentration in the pus is above 8.5 mg/L. 1-2 hours after oral administration, the blood drug concentration reaches its peak and the effective concentration can be maintained for 12 hours. The blood drug concentrations after oral administration of 0.25g, 0.4g, 0.5g, and 2g were 6, 9, 12, and 40 mg/L, respectively. This product is excreted 60-80% through the kidneys, with about 20% of the prototype drug excreted in urine. The rest is excreted in the form of metabolic products (25% glucuronic acid conjugates, 14% other metabolic conjugates) in urine, 10% excreted in feces, and 14% excreted through the skin.

【Storage】Protect from light and store in a sealed container.

【Package】Oral solid drug, packed in high-density polyethylene bottle, 21 tablets per bottle, or 100 tablets per bottle.

【Validity】36 months.

【Standard】Ch.P. 2020, Supplementary Edition 1.

【Drug approval number】Guoyao Zhunzi H12020297