pharmacological action:             
Ampicillin is a semi synthetic broad-spectrum penicillin. Its antibacterial mechanism is to prevent bacterial cell wall synthesis, so it can not only inhibit its proliferation, but also directly kill bacteria. Its effect on Gram-positive bacteria was similar to that of penicillin, and its effect on Streptococcus viridis and Enterococcus was better than that on other bacteria, but it was not effective on penicillin resistant Staphylococcus aureus. Among the Gram-negative bacteria, Neisseria gonorrhoeae, meningococci, influenza bacilli, pertussis, Escherichia coli, typhoid and paratyphoid bacilli, dysentery bacilli, Proteus mirabilis, Brucella, etc. are sensitive to the drug, but easy to produce drug resistance. Pneumoniae, indole positive Proteus and Pseudomonas aeruginosa were not sensitive to this product.

Indication:            
This product is mainly used for urinary system, respiratory system, biliary tract, intestinal tract infection caused by sensitive bacteria, meningitis, endocarditis, etc.Ampicillin for Injection, USP is indicated in the treatment of infections caused by susceptible strains of the designated organisms in the following conditions:
Respiratory tract Infections caused by S. pneumoniae (formerly D. pneumoniae). Staphylococcus aureus(penicillinase and nonpenicillinase-producing), H. influenzae, and Group A beta-hemolytic Streptococci.
Bacterial Meningitis caused by E. coli, Group B Streptococci, and other Gram-negative bacteria (Listeria monocytogenes, N. meningitidis). The addition of an aminoglycoside with ampicillin may increase its effectiveness against Gram-negative bacteria.
Septicemia and Endocarditis caused by susceptible Gram-positive organisms including Streptococcussp., penicillin G-susceptible staphylococci, and enterococci. Gram-negative sepsis caused by E. coli, Proteus mirabilis and Salmonella sp. respond to ampicillin. Endocarditis due to enterococcal strains usually respond to intravenous therapy. The addition of an aminoglycoside may enhance the effectiveness of ampicillin when treating streptoccoccal endocarditis.
Urinary Tract Infections caused by sensitve strains of E. coli and Proteus mirabilis.
Gastrointestinal Infections caused by Salmonella typhosa (typhoid fever), other Salmonella sp., and Shigella sp. (dysentery) usually respond to oral or intravenous therapy.


Contraindication:            
It is forbidden to use ampicillin or other penicillin allergies, and should be avoided in patients with infectious mononucleosis, cytomegalovirus infection, lymphocytic leukemia and lymphoma.

Adverse reactions:           
The adverse reactions of ampicillin were similar to those of penicillin, and the allergic reactions were common skin rash and urticaria, which were higher than other penicillins. Anaphylactic shock, neutropenia and thrombocytopenia were occasionally seen. Neurologic symptoms such as convulsion could occur after intravenous administration of large dose of drugs.           
The most common adverse reactions of ampicillin were allergic reactions.           
1.Rash is the most common adverse reaction. It often occurs in 5 days after treatment, and it appears as urticaria or maculopapula. The former is the typical rash of penicillin allergic reaction, and the latter is specific to ampicillin. The incidence of injection was higher than that of oral administration.           
2.Granulocytopenia and thrombocytopenia were occasionally seen after treatment.            3. Interstitial nephritis can occur in a few patients.           
3.Liver function abnormality was occasionally seen in a few patients.           
4.Nervous system toxic symptoms such as convulsion may occur after large dose intravenous administration. After medication, the infants may have increased intracranial pressure, showing the protrusion of anterior fontanelle.           
6. Ampicillin associated enteritis is extremely rare.