Hexamycin should refer to Chloramphenicol, an amidol antibiotic, which can be used to treat infections of gram-negative bacteria with some anti-infective effects. Chloramphenicol is more effective in the treatment of cocci and bacilli, such as meningococcus and streptococcus pneumoniae, which can be used for the infection of the organism due to cocci and bacilli. Besides, chloramphenicol has therapeutic effect on salmonella typhi, chlamydia and other infections, and it can kill the bacteria with rational use. Chloramphenicol also has a certain therapeutic effect on bacterial infections of the respiratory system and urinary system. Chloramphenicol has relatively large side effects and a small range of use, and must be taken correctly under the guidance of a doctor, and must not be used without authorization or unauthorized increase or decrease in dosage. Abuse of chloramphenicol may cause greater side effects on the human skeletal system and blood system. Possible adverse reactions of taking Chloramphenicol are nosebleed, skin petechiae and ecchymosis, nausea, vomiting, diarrhea and so on. Contraindications to taking Chloramphenicol are children, pregnant and breastfeeding women, people with liver or kidney disease, people who are allergic to Chloramphenicol, and people with immune system dysfunction.