| the third generation cephalosporin | cefmenoxime is a semi-synthetic third generation cephalosporin, and its antibacterial spectrum is similar to that of cefotaxime. It has antibacterial effects on G-and G aerobic and anaerobic bacteria. In G-bacteria, the antibacterial power against Escherichia coli and Pneumonia is slightly stronger than that of cefotiam, which is significantly stronger than that of the first generation cefazolin; it is also stronger than that of influenza bacillus, Proteus, Sarratia mucosae, Citrobacter and Enterobacter. In G + bacteria, Streptococcus pyogenes, pneumococcus than cefotiam, cefazolin are stronger. It also has strong antibacterial activity against Streptococcus in the digestive tract. Relatively speaking, the effect on Staphylococcus is not as good as the first and second generation cephalosporins. The effect on Pseudomonas aeruginosa, Enterobacter and Enterococcus is poor. The main mechanism of action of this product is to hinder the synthesis of bacterial cell walls. It has a strong active effect on G-bacteria because its cell wall has good permeability to this product. There is a dose-dependent blood concentration during intravenous injection, that is, the concentration increases with the increase of the dose. It is almost not metabolized in the body, and it is well transported to various tissues and body fluids, and the concentration in bile is higher. After intramuscular injection of 0.5g, the peak blood drug concentration was 11mg/L after 30 minutes. The blood drug concentration can reach 99.4mg/L within a few minutes after intravenous injection of 1g and 2g. After intravenous drip of 1g and 1 hour, the blood drug concentrations were 50mg/L and 135mg/L respectively. The plasma protein binding rate was 69% ~ 85%. It is well distributed in the body. The drug concentration in the tissue exceeds the minimum inhibitory concentration of pathogenic bacteria. The drug concentration in bile can reach 249mg/L after intravenous injection of 1g. It can also enter the cerebrospinal fluid of patients with meningitis, and its drug concentration can reach 11% ~ 18% of the serum concentration. There are also high concentrations in the uterus, ovaries, and pelvic exudates, and there are certain concentrations in cord blood, amniotic fluid and milk. It is mainly excreted in urine through the kidney in its original shape, and about 80% of the dose is excreted in urine within 24 hours. The half-life of serum is 0.9~1.2 hours. Repeated administration has no savings. The half-life is prolonged during renal dysfunction. Indications: This product is suitable for cefmenoxime-sensitive Streptococcus (except Enterococcus), Streptococcus pneumoniae, Digestive Streptococcus, Escherichia coli, Citrobacter, Klebsiella, Enterobacter, Serratia, Proteus, Haemophilus influenzae, Bacteroides, etc. caused by the following infections: 1. Pneumonia, bronchitis, bronchiectasis complicated with infection, secondary infections of chronic respiratory diseases; lung abscess, empyema; 2. Pyelonephritis, cystitis; vestibular adenitis, endometritis, adnexitis, pelvic inflammatory disease, parauterine tissue inflammation; 3. Cholangitis, cholecystitis, liver abscess; peritonitis; 4. Burns, Secondary infection of surgical trauma; 5. Septicemia; 6. Cerebrospinal meningitis. |
| adverse reactions | 1. serious adverse reactions:(1) sometimes cause shock (less than 0.1%), so careful observation should be made. if there are abnormal symptoms such as discomfort, abnormal feeling in the mouth, wheezing, dizziness, defecation, tinnitus, sweating, etc., drug administration should be stopped and appropriate treatment should be carried out. (2) Occasionally acute renal insufficiency and other severe renal dysfunction (less than 0.1%), so it is necessary to check renal function regularly and observe carefully. If it is abnormal, stop the administration and carry out appropriate treatment. (3) Sometimes granulocytopenia (less than 0.1% ~ 5%) or agranulocytosis (less than 0.1%) occurs. In addition, other cephalosporins have reports of hemolytic anemia. When abnormalities occur, the administration should be stopped and appropriate treatment should be carried out. (4) Sometimes severe colitis (less than 0.1%) accompanied by bloody stools such as pseudomembranous colitis occurs. If abdominal pain or multiple diarrhea occurs, the administration should be stopped immediately and appropriate treatment should be carried out. (5) Interstitial pneumonia and PIE syndrome (less than 0.1%) accompanied by fever, cough, dyspnea, chest X-ray abnormalities, eosinophilia, etc., when this symptom occurs, stop the administration and carry out Appropriate treatment. (6) For patients with renal insufficiency, when a large amount of medication is used, it sometimes causes spasm. 2. Other adverse reactions:(1) Allergy: rash, urticaria, erythema, itching, fever, lymphadenopathy, arthralgia;(2) Blood: anemia, eosinophilia, thrombocytopenia;(3) Liver: ALT, AST, ALP, LDH, jaundice, gamma-GTP;(4) Digestive tract: diarrhea, nausea, vomiting, loss of appetite, abdominal pain;(5) Flora disorders: stomatitis, candidiasis;(6) Vitamin deficiency: symptoms of vitamin K deficiency (hypozymogenemia, bleeding tendency, etc.), symptoms of vitamin B deficiency (glossitis, stomatitis, loss of appetite, neuritis, etc.);(7) Others: fatigue, staggering, headache. Fig. 1 is the structural formula of cefmenoxime |
| taboo | Those with a history of allergic reactions to this product and cephalosporins are prohibited. |
| Precautions | 1. The following patients should be used carefully (1) Patients with a history of allergy to penicillin antibiotics;(2) I or my parents and brothers are easy to cause bronchial asthma Patients with allergic symptoms such as rash and urticaria;(3) Patients with severe renal dysfunction (there is a possibility of continuous increase in blood drug concentration);(4) Elderly patients (decreased physiological function, prone to side effects; sometimes vitamin K deficiency and bleeding tendency);(5) Those with poor oral feeding or intravenous nutrition, and those with poor general state (sometimes it can cause vitamin K deficiency, so it should be carefully observed). 2. Due to the possibility of shock reaction, detailed consultation is required. It is recommended to do a skin allergic reaction test before injection. First aid should be done in advance in case of shock. 3. When using this product, it is best to do liver function, kidney function, blood and other tests regularly. 4. Interference with diagnostic reagents: In addition to the urine sugar test tape (TES-tape) reaction, false positive reactions may occur when urine sugar is measured with Banchley's reagent, Flynn's reagent, and Clinitest (sheet reagent containing copper sulfate). The direct anti-globulin (Coombs) test is positive, please pay attention. (2016-03-11) |
| drug interaction | 1. furanilic acid diuretic: it has been reported that the combination with other cephalosporin antibiotics can aggravate renal dysfunction, so renal function should be paid attention to when combined. 2. Ethanol (drinking): alcohol intake from drinking, sometimes flushing, nausea, tachycardia, hyperhidrosis, headache, etc., so alcohol intake should be avoided during and at least one week after medication. |
| use | cephalosporins broad-spectrum antibiotics have strong activity against gram-negative bacteria and are stable to β-lactamase. they must be injected and administered. Clinically used for respiratory tract infections caused by sensitive bacteria, urinary tract infections, female genital infections, biliary tract infections, peritonitis, surgery, gynecology and ENT diseases. |
| production method | method 1: cefotaxime is used as raw material. The trifluoroacetate of cefotaxime is dissolved in 272rng 1-methyl -5-mercapto. 1H-tetrazole, 555mg sodium bicarbonate, 68mg triethylphenylammonium bromide and 10ml water in a solution, in a nitrogen atmosphere, at 60 degrees C reaction for 6h. Cooling, and through the column equipped with Amberlite XAD-2, first use water, and then use 2.5% ethanol to unfold, that is, the sodium salt of cefmenoxime, the melting point is 174-175 ℃ (decomposition). Method 2: Compound (I) and triethylamine are dissolved in 50% tetrahydrofuran aqueous solution. Under the cooling of ice bath, tetrahydrofuran solution of compound (II) is added dropwise (see cefotaxime sodium for the preparation method). After adding, stir for 1h at room temperature. Water and ethyl acetate were added, and the water layer was adjusted to Ph = 2.0 with phosphoric acid. After shaking, the organic layer is separated, and the water layer is extracted with ethyl acetate. The organic layers were combined and the compound (III) was obtained after conventional treatment. Dissolve compound (III) in dimethylacetamide (hydrazine chamber), add thiourea, and stir at room temperature for 15h. Pour into ice water and adjust to Ph = 3.5 with sodium bicarbonate. Filter to collect the precipitated solid, dissolve in 5% sodium bicarbonate aqueous solution, perform chromatography with Amberlite XAD-2, elute with water and then use 2% ethanol aqueous solution, and freeze-dry to obtain cefmenoxime sodium. |
