【Main Components】 Disodium Hydrogen Chlortetracycline Sulfate

【Properties】 This product is a white or off-white powder.

【Pharmacological Effects】 Pharmacodynamics: Disodium Hydrogen Chlortetracycline belongs to the aminoglycoside antibiotics. It interferes with the bacterial protein synthesis process, causing abnormal protein synthesis, hindering the release of already synthesized proteins, and also increasing the permeability of the bacterial cell membrane, resulting in the leakage of some important physiological substances, ultimately causing bacterial death. Chlortetracycline has antibacterial effects against Mycobacterium tuberculosis and various Gram-negative bacteria, such as Escherichia coli, Salmonella, Brucella, Bacillus, Shigella dysenteriae, and Nocardia. It has poor effects on most Gram-positive cocci, such as Staphylococcus aureus. Streptococcus, Pseudomonas aeruginosa, and anaerobic bacteria have inherent resistance to this drug.

Pharmacokinetics: Intramuscular injection has good absorption. The peak concentration in the blood reaches its maximum within 0.5 to 2 hours. Under therapeutic doses, the effective concentration in the blood generally maintains for 6 to 12 hours. It is mainly distributed in extracellular fluid and exists in various organs of the body, with the highest concentration in the kidneys, less in the lungs and muscles, and almost undetectable in brain tissue (about 4% of the serum concentration for horses). It can reach bile, pleural effusion, ascites, and tuberculous cavities and caseous tissues, and can also pass through the placental barrier. The protein binding rate is 20% to 30%. Most of this drug is excreted by the glomerular filtration in the kidneys in its original form, with high concentrations in urine, and a small amount is excreted in bile. The half-life in horses, water buffaloes, cattle, dairy goats, and pigs is 3.1, 2.4, 4.1, 4.71, and 3.8 hours, respectively.

【Drug Interactions】 ① It has a synergistic effect when used with penicillins or cephalosporins. ② This type of drug has enhanced antibacterial effects in an alkaline environment and can enhance the antibacterial efficacy when used with alkaline drugs (such as sodium bicarbonate, aminophylline, etc.). However, its toxicity also increases accordingly. When the pH value exceeds 8.4, the antibacterial effect is weakened. ③ Cations such as Ca2+, Mg2+, Na+, NH, and K+ can inhibit the antibacterial activity of this type of drug. ④ When used with cephalosporins, dextran, potent diuretics (such as furosemide), erythromycin, etc., it can enhance the ototoxicity of this type of drug. ⑤ Muscle relaxants (such as succinylcholine) or drugs with such effects can strengthen the neuromuscular blocking effect of this type of drug.

【Actions and Indications】 Antibiotic drugs. Used for infections caused by Gram-negative bacteria and Mycobacterium tuberculosis.

【Usage and Dosage】 Measured in chlortetracycline. Intramuscular injection: One-time dose, 10 mg per 1 kg of body weight. Twice a day.

【Adverse Reactions】 (1) The ototoxicity of chlortetracycline is relatively strong. The most common cause is vestibular damage, which can worsen with the accumulation of the drug over time and is dose-dependent.

(2) Cats are more sensitive to chlortetracycline, and a large dose can cause nausea, vomiting, salivation, and ataxia.

(3) Excessive dosage of chlortetracycline can easily lead to neuromuscular blocking effects. When combined with penicillin and chlortetracycline for infection prevention during surgical anesthesia in dogs and cats, accidental death occurs frequently, which is due to the enhanced effect of general anesthetics and muscle relaxants on neuromuscular blocking.

(4) Long-term use can cause kidney damage. 

【Notes】 (1) Bisdihydrostreptomycin has cross-allergic reactions with other aminoglycosides. It is prohibited for use in animals that are allergic to aminoglycosides. 

(2) Use with caution when the animal shows signs of dehydration (which may lead to an increase in blood drug concentration) or renal dysfunction.

(3) When using this product to treat urinary tract infections, carnivorous and omnivorous animals can simultaneously take sodium bicarbonate orally to make the urine alkaline, thereby enhancing the efficacy of the drug.

【Withdrawal Period】 Cattle, sheep, and pigs: 18 days; Milk withdrawal period: 72 hours.

【Specification】 (1) 0.75g (750,000 units)  (2) 1g (1,000,000 units)  (3) 2g (2,000,000 units)