Amoxicillin is one of the most commonly used semisynthetic penicillin broad-spectrum β-lactam antibiotics.
【Function and use】
The antibacterial spectrum of amoxicillin is similar to ampicillin, but the effect is fast and strong, and the absorption by internal medicine is good, which is better than ampicillin. Amoxicillin is more resistant to acid than ampicillin, but it cannot be used for the treatment of meningitis. Amoxicillin has a strong effect on most Gram-negative bacteria such as E. coli, Salmonella, Proteus, Pasteurella, Haemophilus parahaemolyticus. It has strong antimicrobial activity against a variety of Gram-positive bacteria (including cocci and bacilli), spirochetes, actinomycetes, leptospira, etc.It has strong antimicrobial activity against a variety of Gram-positive bacteria (including cocci and bacilli), spirochetes, actinomycetes, leptospira, etc. It is ineffective for viruses, mycoplasma, chlamydia and other bacteria without cell wall.
【Mechanism of action】
Amoxicillin has a strong bactericidal effect and is also capable of penetrating the cell wall. Immediately after oral administration, the lactam group in the drug molecule is hydrolyzed to form a peptide bond, which is rapidly inactivated by binding to a transpeptidase in the cell, and the only way to cleave the cell body by using the transpeptidase to synthesize the glycopeptide is to sterilize the bacteria. The cells rapidly become spheroids and rupture and dissolve. The cells are eventually lost due to cell wall, and the water continuously penetrates and swells and dies. Strong antibacterial and/or bactericidal action against most pathogenic G+ and G-bacteria including cocci and bacilli.
The absorption rate of amoxicillin in the gastrointestinal tract is about 90%, which is more rapid and complete than that of ampicillin. The single stomach animal (such as pig) absorbs 74~92% after oral administration, The content of gastrointestinal tract affects its absorption rate, but does not affect its absorption degree, so it can be administered by mixed drinking and feeding. After oral administration of the same dose, the blood concentration of amoxicillin was 1.5-3 times higher than that of ampicillin.
In production, many preparations contain potassium clavulanate, whose main function is to relieve the resistance of bacteria to amoxicillin, and the direct synergistic effect is minimal. Potassium clavulanate is very unstable, and it is easily destroyed by water. Therefore, whether it is administered by drinking water or mixed feed, the effect of potassium clavulanate may be small.
Amoxicillin is a time-dependent antibiotic, so the antibacterial effect depends mainly on the duration of the effective concentration of the drug in the tissue or blood.
【Common shortcomings of amoxicillin】
1. Low solubility. The maximum solubility of amoxicillin is very limited, it can only reach 2g/L water, and it can complex with the chelate in water to form a precipitate, thus affecting the effect of drinking water.。
2. Chemical instability. Amoxicillin is a very fragile molecule that is easily degraded when exposed to water. It is more unstable in acid and alkali, and the β-lactam ring is opened to form inactive molecules such as penicillin. Its stable pH range is 7~8. Therefore, water solubility and stability are a contradiction.
3. Poor palatability. Amoxicillin itself has a bitter taste, thus affecting palatability, resulting in insufficient intake of medicine.
4. Block the drinking water pipe. Because the solubility is not good, or the influence of water quality, it can form a precipitate and block the pipeline; the preparation with sugar as an auxiliary material can easily form a biofilm in the drinking water pipeline, affecting the water quality.
Commonly used in the respiratory tract, digestive tract, urinary tract, soft tissue and systemic infection caused by sensitive bacteria; good effect on lung infection.
Clinically, it is commonly used to prevent and treat pig pneumonia, bronchitis, streptococcosis, swine erysipelas, haemophilus parasuis, actinobacillus pleuropneumonia, E. coli, red scour of piglets and so on. Also commonly used to treat or prevent mastitis, endometritis, and postpartum lactation in sows.
1. Probenecid can delay the excretion of amoxicillin by renal excretion (competitive reduction of renal tubular secretion of amoxicillin), prolong its serum half-life, thus increasing the blood concentration of this product.
2. When amoxicillin is combined with aminoglycosides (except gentamicin) and peptides (such as colistin), it can enhance the in vitro bactericidal effect of amoxicillin on streptococcus faecalis at sub-inhibitory concentration.
3. When amoxicillin is combined with a β-lactamase inhibitor such as potassium clavulanate, the antibacterial effect is significantly enhanced.
4. Florfenicol, macrolides, sulfonamides, gentamicin and tetracycline can interfere with the antibacterial effect of this product in vitro, but its clinical significance is unknown, preferably separate administration.
5. It should be used separately or intermittently with vitamin C, vitamin B, roxithromycin, aminophylline, potassium permanganate, chlorpromazine hydrochloride, hydrogen peroxide or antagonistic effect or side effects.
【Comparison of Anlisu and similar preparations】
Table1 Comparison of Anlisu and similar preparations
Ordinary domestic preparation30%
Simple mixing, dilution
Stability in water
Does not degrade within 3 hours
Degradation of 15% in 3 hours
Does not degrade within 3 hours
More than 12 hours
Within 8 hours
More than 12 hours
Number of doses per day
100ml water can dissolve 30% Anlisu at least 4 grams
1. Storage stability: Anlisu uses imported excipients and advanced preparation technology to keep it at room temperature for 800 days to ensure the stability of drug storage.
2. Dissolution does not degrade: it is not damaged by any water quality. Adding unique excipients can adjust the pH value in drinking water to between 7 and 8 to improve solubility and stability. In addition, the special components in the excipients can adjust the hardness of water and capture ions with chelating action to form soluble complexes, so as to avoid complexing amoxicillin molecules and maintain its original solubility. After 24 hours of water dissolution, the active ingredient content is still as high as 90% or more, while the common amoxicillin preparation or amoxicillin trihydrate is degraded to less than 85% in 3 hours.
Figure 2 Comparison of the stability of different amoxicillin soluble powders in tap water at room temperature (compared with domestic similar products, 30% Anlisu is more stable in water)
Figure 3 Stability of different amoxicillin-soluble powders in gastric acid (30% stability of Anlisu in gastric acid is similar to that of imported similar products, and is significantly better than domestic similar products)
The dissolution rate refers to the rate and extent of release of the pharmaceutically active ingredient from the preparation in a prescribed solvent, and the higher the dissolution rate, the higher the absorption utilization rate. The dissolution rate of Anlisu and imported products is higher than that of domestic similar products, so the effect is better.
After oral administration of Anlisu, it can be absorbed rapidly and reach the peak of blood concentration faster than that of common domestic preparations. Moreover, the concentration of Anlisu in blood lasts longer than that of most pathogenic bacteria for 12 hours, so the efficacy of amlidin is lasting. Drugs are given by drinking water once a day.
【Usage and dosage】
Uasage: Feed or water medication.
Dosage: 5~10mg/kg body weight, once a day.
Prevention: Feed medication, adding 300g of this product per ton of feed for 3 to 5 days;
Treatment: Water medication, 160g/ton of water, once a day, for 3 to 5 days, If you take the medicine for 8 hours a day, you can concentrate the whole day's dosage within 8 hours. Feed medication, growing fattening pigs 400 g/ton of this product, used for 3 to 5 days; lactating sows 400 g/ton of this product, used for 3 to 5 days; boar and limited-feeding pregnant sows 600 g/ton of feed, used for 3 to 5 days.
1. Storage stability: Anlisu stored at room temperature for 800 Days.
2. Stable after water dissolution, high dissolution: Not affected by water quality, can dissolve more than 4 grams per 100ml of water, and 24 hours after water dissolution, the active ingredient is still more than 90%.
3. Resistant to stomach acid: More than 90% of the active ingredients remain in gastric acid for 2 hours.
4. Long-term effect: Once administered, the effective blood concentration of most pathogenic bacteria can be maintained for more than 12 hours (common domestic preparations only 6 to 8 hours). Therefore, it can be administered once a day by drinking water.
5. Less dosage: Due to its high bioavailability and good stability, the dosage is only 1/3 of that of ordinary domestic preparations.
6. Good palatability: It does not affect drinking water administration and mixed feeding administration.