Doxicolin aqua is a combined broad-spectrum antimicrobial veterinary product active against Streptococcus spp., Haemophilus spp., Escherichia coli, Clostridium spp., Listeria monocytogenes, Actinomyces spp., Enterobacter spp., Staphylococcus spp., Yersinia spp., Rickettsia spp., Mycoplasma spp., Bordetella spp., Pasteurella spp., Salmonella spp., Klebsiella spp. and others. Pseudomonas aeruginosa, Proteus spp., Serratia spp., most strains of Bacteroides fragilis are hyposensitive to the veterinary product action.

Doxycycline hyclate is an antibiotic from the group of semi-synthetic tetracyclines. Acts on gram-positive and gram-negative microorganisms. The mechanism of action is based on inhibition of the synthesis of nucleic acids and proteins of a bacterial cell.

Colistin sulphate is a cyclic polypeptide antibiotic synthesized by the aerobic spore-forming bacillus Bacillus polymyxa and acting on gram-negative microorganisms. The mechanism of action of colistin sulphate is to disrupt the permeability of the bacterial cell wall by combining with lipoproteins, which leads to the loss of amino acids, inorganic ions, purines and pyrimidines, leading to the death of the bacterial cell. Colistin sulphate reduces the effect of bacterial endotoxins in tissue fluids.

After oral administration, doxycycline is well absorbed in the gastrointestinal tract, reaching therapeutic plasma concentrations after 2 hours and remaining at a therapeutic level for 18-20 hours, easily penetrates into most organs and tissues, splitting in the liver with the formation of inactive metabolites, excreted from the body mainly in urine. By binding to blood proteins, it easily penetrates into most tissues. Colistin sulphate is practically not absorbed in the gastrointestinal tract and does not accumulate in muscle tissue and eggs; it is excreted from the body in faeces.

The veterinary product is characterized by high bioavailability and low toxicity. It is excreted from the body mainly in faeces and urine.