Tetracycline hydrochloride is a kind of broad spectrum antibiotics, high concentration has the effects of sterilization, in addition to the common gram-positive bacteria and gram-negative bacteria and anaerobic bacteria, the majority of rickettsia, mycoplasma, chlamydia, and atypical mycobacteria, helix, actinomycetes, bacillus anthracis, monocytosis listeria, clostridium, slave card bacteria sensitive to belong to our product. This product is more effective against GRAM-positive bacteria than GRAM-negative bacteria, but Enterococcus and penicillin-resistant GONococcus are resistant to it.