Nitroimidazoles
Generic name: Metronidazole injection
Trade name: Jial sodium
Pharmacology and Toxicology
Metronidazole has a strong antibacterial effect on most anaerobic bacteria, but has no effect on aerobic bacteria and parthenogenic anaerobic bacteria, the antibacterial spectrum includes Bacteroides fragilis and other Bacteroides spp. Its bactericidal concentration is slightly higher than the inhibition concentration.
It can also inhibit the redox reaction of amoeba and break the nitrogen chain of the protozoa. In vitro test proves that the concentration of 1~2mg/L, the morphology of amoeba lysate can be changed in 6~20 hours, and all of them can be killed in 24 hours, and the concentration of 0.2mg/L can kill amoeba lysate in 72 hours. This product has a powerful effect of killing trichomonas, the mechanism is not known.
It has carcinogenic effect on some animals.
Pharmacokinetics
The peak is reached rapidly after intravenous administration. Protein binding rate <5%, after absorption, widely distributed in various tissues and body fluids, and can pass the blood-brain barrier, the effective concentration of the drug can appear in saliva, placenta, bile, milk, amniotic fluid, semen, urine, pus and cerebrospinal fluid. It has been reported that the concentrations of drugs in placenta, breast milk and bile are similar to blood concentrations. The blood concentration in cerebrospinal fluid of healthy human is 43% of the blood concentration in the same period. The effective concentration can be maintained for 12 hours. The product is excreted by the kidney in 60% to 80%, about 20% of the original form is excreted in the urine, the rest is excreted by the urine in the form of metabolites (25% is glucuronide conjugate, 14% is other metabolic conjugate). 10% is excreted in the feces. 14% is excreted from the skin.
Indications】This product is mainly used for the treatment of anaerobic bacterial infections.
Dosage and Administration
Intravenous drip.
(1) Adult dosage: for anaerobic bacterial infection, the first intravenous dose is 15mg/kg (1g for 70kg adults), and the maintenance dosage is 7.5mg/kg, once every 6-8 hours.
(2) Pediatric dosage: The injection dosage for anaerobic bacterial infection is the same as that for adults.
Adverse reactions
Adverse reactions occur in 15%-30% of cases, with gastrointestinal reactions being the most common, including nausea, vomiting, loss of appetite, abdominal cramps, which generally do not affect treatment; neurological symptoms include headache, vertigo, occasional abnormal sensation, limb numbness, ataxia, polyneuritis, etc. High doses can cause convulsions. In a few cases, urticaria, flushing, pruritus, cystitis, urinary difficulties, metallic taste in the mouth and leukopenia, etc., are reversible and recover on their own after discontinuation of the drug.
Contraindications】Contraindicated in patients with active central nervous system disorders and blood disorders.
Precautions
(1) Interference with diagnosis: The metabolites of this product may cause the urine to appear dark red.
(2) The dose should be reduced in patients with pre-existing liver disease. Discontinue if movement disorders or other central nervous system symptoms occur. A white blood cell count should be done before repeating a course of treatment. For anaerobic infections combined with renal failure, the dosing interval should be extended from 8 hours to 12 hours.
(3) This product can inhibit the metabolism of alcohol, so alcohol should be abstained during the drug administration.
Pregnant women and nursing mothers】Pregnant women and nursing mothers are prohibited.
For elderly patients
The pharmacokinetics of this product may be altered in the elderly due to reduced hepatic function, so the blood concentration of this product should be closely monitored.
Drug Interactions
(1) This product can inhibit the metabolism of warfarin and other oral anticoagulants, enhance their effects and cause prolongation of prothrombin time.
(2) Simultaneous application of phenytoin sodium, phenobarbital and other drugs that induce liver microsomal enzymes can enhance the metabolism of this product, resulting in a decrease in blood concentration and a slow excretion of phenytoin sodium.
(3) Simultaneous application of cimetidine and other drugs that inhibit hepatic microsomal enzyme activity can slow down the metabolism and excretion of this product in the liver and prolong the serum half-life of this product, and the dose should be adjusted according to the results of blood concentration measurement.
(4) This product interferes with the metabolism of disulfide, and psychiatric symptoms may appear after drinking alcohol in patients who use disulfiram within 2 weeks, so this product should not be used again.
(5) This product can interfere with the results of aminotransferase and LDH measurement, and can cause cholesterol and triglyceride levels to decrease.
Overdose】High dose can cause convulsions.
Specification】0.915g
Retail Price】：16.10/pc
【Reimbursement Category】：Publicly funded
Drug Name (Generic Name): Metronidazole for Intravenous Injection
Pharmacology and Toxicology
This product is a precursor drug of metronidazole, which is hydrolyzed in the body to produce the corresponding amount of metronidazole.
Metronidazole has a strong antibacterial effect on most anaerobic bacteria, but has no effect on aerobic bacteria and parthenogenic anaerobic bacteria. The antibacterial spectrum includes Bacteroides fragilis and other Bacteroides, Clostridium, Clostridium perfringens, Mycobacterium, Veronococcus, Streptococcus, and others. The bactericidal concentration is slightly higher than the bacteriostatic concentration.
The bactericidal mechanism of metronidazole has not been fully elucidated, and the nitroreductase of anaerobic bacteria plays an important role in the energy metabolism of sensitive strains. The nitro reductase of this product becomes a cytotoxic, thus acting on the DNA metabolic process of bacteria and promoting cell death.
Pharmacokinetics]
After entering the body, the product is rapidly hydrolyzed into metronidazole and phosphate. After intravenous injection of 0.915g, the time to peak of metronidazole in plasma (Tmax) is about 10-20 minutes, and the peak blood concentration (Cmax) is about 50μg/ml. After hydrolysis into metronidazole, it is widely distributed in tissues and body fluids, and can pass the blood-cerebrospinal fluid barrier. The drug can reach effective concentration in saliva, bile, milk, amniotic fluid, semen, urine, pus and cerebrospinal fluid. The concentrations in placenta, milk and bile are similar to those in plasma. The protein binding rate is less than 20%. Mainly metabolized in the liver. The half-life of blood elimination (t1/2β) is 9~11 hours, 60%~80% is excreted by kidney, of which 20% is in original form and the rest is metabolite (25% is glucuronide conjugate, 14% is other metabolic conjugate). 10% is excreted with feces, 14% is excreted from skin.
Indications
Used for various infectious diseases caused by anaerobic bacteria, such as sepsis, endocarditis, abscess chest, lung abscess, abdominal infection, pelvic infection, gynecological infection, bone and joint infection, meningitis, brain abscess, skin soft tissue infection, etc.
Dosage
Intravenous drip. 0.915g once, dissolve in 100ml of sodium chloride injection or 5% glucose injection, and drip slowly within 1 hour, once every 8 hours, 7 days as a course of treatment.
Adverse reactions
1, the most serious adverse reactions of this product is the high dose can cause seizures and peripheral neuropathy, the latter mainly manifested as limb numbness and abnormal sensation. In some cases, long-term use of the drug can produce persistent peripheral neuropathy.
2. Other common adverse reactions are.
(1) Gastrointestinal reactions, such as nausea, loss of appetite, vomiting, diarrhea, abdominal discomfort, change in taste, dry mouth, metallic taste in the mouth, etc.
(2) Reversible granulocytopenia.
(3) Allergic reactions, rash, urticaria, pruritus, etc.
(4) Central nervous system symptoms, such as headache, vertigo, syncope, abnormal sensation, numbness of limbs, ataxia and confusion.
(5) Local reactions such as thrombophlebitis, etc.
(6) Other reactions such as fever, vaginal candida infection, cystitis, difficulty in urination, dark urine, etc. are reversible and recover on their own after stopping the drug.
Contraindications】It is contraindicated in patients with hypersensitivity to this product or pyrrole drugs and in patients with active central nervous system diseases and hematological diseases.
Precautions
1, carcinogenic, mutagenic effects: animal tests or in vitro assays found that the product has carcinogenic, mutagenic effects, but not confirmed in humans.
2, the use of central nervous system adverse reactions, should be promptly discontinued.
3. This product can interfere with the test results of alanine aminotransferase, lactate dehydrogenase, triglyceride, hexokinase, etc., so that their measured values are reduced to zero.
4. Alcoholic beverages should not be consumed during the medication period because they can cause the accumulation of acetaldehyde in the body, interfere with the oxidation process of alcohol and lead to disulfiram-like reactions, and patients may experience abdominal cramps, nausea, vomiting, headache and facial flushing.
5. The metabolism of this product is slowed down in people with reduced liver function, and the drug and its metabolites tend to accumulate in the body, so the dosage should be reduced and the blood concentration should be monitored.
6, the product can be continuously cleared from the gastric juice, some placed gastric tube for suction decompression, can cause a decrease in blood concentration. During hemodialysis, the product and metabolites are cleared rapidly, so the application of this product does not require dose reduction.
7, Candida infection, the application of this product, its symptoms will be aggravated, need to give antifungal treatment at the same time.
8, anaerobic bacterial infection combined with renal failure patients, the dosing interval should be extended from 8 hours to 12 hours.
9.This product should not come into contact with needles and cannulae containing aluminum, and avoid dripping with other drugs.
10.White blood cell count should be done before repeating a course of treatment.
Pregnant women and nursing mothers
Metronidazole, the hydrolysate of this product, can cross the placenta and enter the fetal circulation rapidly. Animal tests have found that intraperitoneal administration is toxic to the fetus, while oral administration is not toxic. The effects of this product on the fetus have not been adequately and closely controlled and are therefore contraindicated in pregnant women.
The concentration of metronidazole in breast milk is similar to that in blood. Metronidazole has been shown to be carcinogenic to young rats in animal studies and should not be used by nursing mothers. If the drug must be used, breastfeeding should be suspended and should not be resumed until 24 to 48 hours after the end of the course of treatment.
Use in children] Children should use with caution and reduce the dosage.
Medication for Elderly Patients
The pharmacokinetics of this product may be altered in the elderly due to decreased hepatic function, and blood levels should be monitored.
Drug Interactions
1. This product can inhibit the metabolism of warfarin and other oral anticoagulants, enhance their effects and cause prolongation of prothrombin time.
2. Combined with phenytoin sodium, phenobarbital and other drugs that induce hepatic microsomal enzymes, it can enhance the metabolism of this product and make the blood concentration decrease, while the excretion of phenytoin sodium is slowed down.
3. Combination with cimetidine and other drugs that inhibit hepatic microsomal enzyme activity can slow down the metabolism and excretion of this product in the liver and prolong the blood elimination half-life (t1/2) of this product, and the dose should be adjusted according to the results of blood concentration measurement.
4, this product can interfere with the metabolism of disulfiram, when the two together, patients may have psychiatric symptoms after drinking alcohol, so the application of disulfiram within 2 weeks should not use this product.
5. This product can interfere with the measurement results of serum aminotransferase and lactate dehydrogenase, and can reduce the level of cholesterol and triacylglycerol.
Specification】250ml/pc
Retail Price】：4.75
【Reimbursement Category】：Publicly funded
Drug Name (Generic Name): Metronidazole Tablets
Pharmacology and Toxicology
This product is a nitroimidazole derivative, which can inhibit the redox reaction of amoeba protozoa and cause the nitrogen chain of protozoa to break. In vitro test proves that the drug concentration of 1~2mg/L, the morphological change of ameba lysate can occur in 6~20 hours, and all of them can be killed within 24 hours, and the concentration of 0.2mg/L can kill ameba lysate within 72 hours. This product has a powerful effect of killing trichomonads, the mechanism of which is not known.
Metronidazole has a killing effect on anaerobic microorganisms, and the metabolites generated when it is reduced in human body also have anti-anaerobic bacterial effects, inhibiting the synthesis of deoxyribonucleic acid of bacteria, thus interfering with the growth and reproduction of bacteria and eventually causing bacterial death.
It has carcinogenic effect on some animals.
Pharmacokinetics]
After oral or rectal administration, the drug is rapidly and completely absorbed, and the protein binding rate is <5%. After absorption, the drug is widely distributed in various tissues and body fluids, and can pass the blood-brain barrier. It has been reported that the concentrations of drugs in placenta, milk and bile are similar to blood concentrations. The blood drug concentration in cerebrospinal fluid of healthy people is 43% of the blood drug concentration in the same period. In a few patients with brain abscess, the drug concentration in pus (34-45 mg/L) is higher than the blood drug concentration (11-35 mg/L) in the same period after taking 1.2-1.8 g daily. The drug concentration in their pus after intra-ear infection was above 8.5 mg/L. The blood concentration peaked 1 to 2 hours after oral administration, and the effective concentration could be maintained for 12 hours. The blood concentration of 0.25g, 0.4g, 0.5g and 2g after oral administration are 6 mg/L, 9 mg/L, 12 mg/L and 40 mg/L respectively. The rest is excreted in urine as metabolites (25% as glucuronide conjugates and 14% as other metabolic conjugates), 10% in feces and 14% in skin.
Indications
For the treatment of intestinal and extraintestinal amoebiasis (such as amoebic liver abscess, pleural amoebiasis, etc.). It can also be used for the treatment of trichomoniasis, microcysticercosis and cutaneous leishmaniasis, dracunculiasis nematode infections, etc. It is also widely used for the treatment of anaerobic bacterial infections.
Dosage
1.Common dosage for adults
(1) intestinal amebiasis, 0.4-0.6g once, 3 times a day for 7 days; extra-intestinal amebiasis, 0.6-0.8g once, 3 times a day for 20 days.
(2) Giardiasis, 0.4g once, 3 times a day, for 5-10 days.
(3) Dracunculiasis, 0.2g once, 3 times a day for 7 days.
(4) Small pouch worm disease, 0.2g once, 2 times a day for 5 days.
(5) For cutaneous leishmaniasis, 0.2g once, 4 times a day for 10 days. Repeat the course of treatment after an interval of 10 days.
(6) For trichomoniasis, 0.2g once, 4 times a day for 7 days; suppositories can be used at the same time, with 0.5g placed in the vagina every night for 7-10 days.
(7) Anaerobic bacterial infection, 0.6~1.2g per day orally, divided into 3 doses, 7~10 days as a course of treatment.
2.Commonly used for children
(1) Amebiasis, 35～50mg/kg per day by weight, divided into 3 times orally, 10 days as a course of treatment.
(2) Giardia, 15-25mg/kg per day by body weight, divided into 3 oral doses for 10 days; the dose for the treatment of dracunculiasis, microcysticercosis and trichinosis is the same as that for Giardia.
(3) For anaerobic bacterial infections, take orally 20-50mg/kg/day according to body weight.
Adverse reactions
Adverse reactions occur in 15%-30% of cases. Gastrointestinal reactions are the most common, including nausea, vomiting, loss of appetite, abdominal cramps, which generally do not affect treatment; neurological symptoms include headache, dizziness, occasional abnormal sensation, limb numbness, ataxia, polyneuritis, etc. High doses can cause convulsions. In a few cases, urticaria, flushing, pruritus, cystitis, urinary difficulties, metallic taste in the mouth and leukopenia, etc., are reversible and recover on their own after discontinuation of the drug.
Contraindications】Contraindicated in patients with active central nervous system disorders and blood disorders.
Precautions
(1) Interference with diagnosis: The metabolites of this product may cause the urine to appear dark red.
(2) The dose should be reduced in patients with pre-existing liver disease. Discontinue if movement disorders or other central nervous system symptoms occur. A white blood cell count should be done before repeating a course of treatment. For anaerobic infections combined with renal failure, the dosing interval should be extended from 8 hours to 12 hours.
(3) This product can inhibit the metabolism of alcohol, so alcohol should be abstained during the drug administration.
Pregnant women and nursing mothers】Pregnant women and nursing mothers are prohibited.
Drug Interaction】This product can enhance the effect of warfarin and other anticoagulant drugs. Combination with hyoscine can interfere with the effect of metronidazole in removing Trichomonas vaginalis.
Drug Overdose】High dose may cause convulsions.
Specification】0.2g*21#
Retail Price】：1.60/bag
【Reimbursement Category】：public expense