Oxytetracycline injection

For assaying oxytetracycline content in injections, tablets, capsules, ointments, and oral suspensions, the United States Pharmacopoeia 28 [1] uses a liquid chromatography method described in the assay under oxytetracycline. For oxytetracycline and Nystatin capsules and for oral suspension, United States Pharmacopoeia 28 [1] uses a microbiological method listed under antibiotics-microbial assays <81>. 

Residue depletion studies in cattle, swine, sheep, chickens, and turkeys given oral forms of oxytetracycline including feed premixes, soluble powders, and tablets showed that residues in all edible tissues, with the exception of kidney, were cleared of detectable amounts of oxytetracycline within 5 days postdose. Injectable forms of oxytetracycline yielded higher residue levels that persisted longer than the oral forms, while long-acting formulations of oxytetracycline required extended withdrawal periods (234). 

Following intramuscular injection of a long-acting oxytetracycline formulation, all sheep tissue residues were below the US tolerance of 0.1 ppm by 14 days after treatment (235). After intramuscular administration to a dairy cow of a single dose of 5 mg oxytetracycline/kg bw, residues were present in milk for as long as 4 days after dosing at concentrations ranging from 370 ppb at day 1 posttreatment to 10 ppb at day 4 posttreatment (233). 

Following a single intramuscular injection of oxytetracycline to European eels at a dosage of 60 mg/kg bw, maximum plasma oxytetracycline concentration (113 ppm) were achieved between 8 and 16 h after administration (240). At 3 weeks after drug administration, highest residue concentrations were in liver (21.7 ppb) and bones (30.2 ppb), whereas kidney, spleen, and muscle contained 6.0, 5.5, and 3.6 ppb. This experiment demonstrated that the pharmacokinetic profile of intramuscularly injected oxytetracycline to eel differed largely from those in rainbow trout, carp, and catfish (241). 

When rainbow trout were kept at 5-10 C, oxytetracycline residues in muscle could be found for 29 days after intraperitoneal injection (4.2 mg/kg bw), for... 

Tetracycline has activity similar but not identical to that of oxytetracycline and chlortetracycline. It may be administered by all the usual routes but absorption from the gastrointestinal tract is better than from intramuscular injection. Blood... 

After a single oral or intravenous administration of tetracycline to chickens at dosage rates of 100 mg/kg or 20 mg/kg bw, respectively, residue concentrations in muscle, kidney, and liver tissues were 0.03, 0.13, and 0.05 ppm, respectively, at 5 days posttreatment (248). Following intramuscular injection of tetracycline and oxytetracycline to goats at a dosage of 15 mg/kg bw at 24 h intervals for 4 days, residual levels of both drugs could be found in milk by day 4 after the last administration (249). The concentration of tetracycline at this time was 0.913 ppm, while that of oxytetracycline was 0.459 ppm in the milk. 

Apart from the pathophysiological condition of the animal, the mode of drug application may also significantly influence the pharmacokinetic profile of a drug (48, 49). For example, drug residues may persist at the injection site for prolonged periods of time (2). In a study in which various sulfonamides and trimethoprim were injected intramuscularly into swine, detectable residues were found at most sites 6 days after the injection, and with the sulfonamides at 30 days in almost half of the animals (50). Other drugs such as dihydrostreptomycin persist for up to 60 days, while positive residues of chloramphenicol are found at 7 days postinjection. Sodium and procaine penicillin, neomycin, tylosin, and oxytetracycline residues have also been determined at 24 h or more postinjection (51). 

The persistence of residues at intramuscular injection sites may be due in part to the irritant response produced in the muscle (52). Chloramphenicol, tylosin, penicillins, dihydrostreptomycin, and oxytetracycline have been shown to produce local irritation at the site of injection, leading to residue persistence this may be exacerbated by the solvent used. However, residues do not persist with proper injection of drugs and use of formulations that do not cause severe irritation (52), as has been demonstrated with one oxytetracycline product that produced little irritation (53-55). 

Oxytetracycline Sustained Release Injectable for i. m. Veterinary Application (2.2 g / 10 ml)... 

Oral 50, 100 mg tablets and capsules 50 mg/5 mL suspension Parenteral 100 mg powder to reconstitute for injection Oxytetracycline (generic, Terramycin)... 

SYNS BISOLVONFYCIN HYDROCYCLIN UQUAMYCIN INJECTABLE NSC-9169 OTETRYN OXLOPAR OXYJECT 100 OXYTETRACYCLINE HYDROCHLORIDE TERAMYCIN HYDROCHLORIDE TETRAMINE TETRAN HYDROCHLORIDE... 

The tetracyclines are amphoteric antimicrobial agents that can form salts with bases or acids (see Chs 1 and 2). Oxytetracycline is a bitter, yellow, odorless crystalline powder. The base is slightly water soluble and the hydrochloride is readily water soluble and is typically administered to horses by slow i.v. injection. It is effective at 5.5 mg/kg once daily for 2 days or more in the treatment of B. equi but is unlikely to completely clear this infection. It is, therefore, used for premunition. Rapid i.v. injection may cause a precipitous drop in blood pressure and collapse owing to the effects of calcium chelation on the myocardium. Intramuscular injection causes objectionable local reactions in horses and should be avoided. Oral administration may be more... 

In some veterinary injectables low molecular weight povidone is combined with 2-pyrrolidone. Typical examples are oxytetracycline [163], ivermectin [628] and sulfonamides [164]. 

Table 91 shows the composition of a commercially available oxytetracycline preparation for injection, that contains povidone as a solubilizing agent. 

Banting, A. de L. Baggot, J.D. (1996) Comparison of the pharmacokinetics and local tolerance of three injectable oxytetracycline formulations in pigs. Journal of Veterinary Pharmacology and Therapeutics, 19, 50-55. 

Nouws, J.F.M. Vree, T.B. (1983) Effect of injection site on the bioavailability of an oxytetracycline formulation in ruminant calves. Veterinary Quarterly, 5, 165-170. 

Aguiar AJ, Armstrong WA, Desai SJ. Development of oxytetracycline long-acting injectable. J Control Release 1987 6 375-385. 

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