Chlortetracycline Hydrochloride is a tetracycline with broad-spectrum antibacterial and antiprotozoal activity. Chlortetracycline hydrochloride (Isphamycin) is bacteriostatic and inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit, thereby preventing the addition of amino acids to the growing peptide chain. This tetracycline is active against a wide range of gram-positive and gram-negative organisms, spirochetes, rickettsial species, certain protozoa and Mycoplasma and Chlamydia organisms.

Chlortetracycline HCl可抑制以下Diplococcus pneuliloniap（MIC：0.098 mg/L）, Streptococcus pyogelles（MIC：0.292 mg/L）, Bacillus subtilis（MIC：0.195 mg/L）, Bacillus subtilis（MIC：0.15 mg/L）, Streptococcus faecalis（MIC：0.3 mg/L）和Mycobacterium ranae（0.3 mg/L）的活性。Chlortetracycline HCl与30S亚基的一个位点亲和力非常高,从而抑制包括专性厌氧菌在内的多种革兰氏阳/阴性菌的活性。