Penicillin and Amoxicillin are not the same. Penicillin belongs to natural antibiotics, while amoxicillin belongs to semi-synthetic penicillin, and there are some differences between the two in terms of antibacterial spectrum, indications and adverse reactions. 1. In terms of antibacterial spectrum, penicillin is effective against gram-negative cocci such as gonococci, gram-positive cocci such as Streptococcus haemolyticus and Streptococcus pneumoniae, gram-positive bacilli such as Listeria monocytogenes, as well as most anaerobic bacilli, but it is ineffective against gram-negative bacilli. Amoxicillin can cover the antibacterial spectrum of penicillin, but also has good antibacterial activity against Streptococcus pyogenes, Salmonella, Escherichia coli, Shigella and Haemophilus influenzae. 2. In terms of indications, penicillin is suitable for all kinds of infections caused by sensitive bacteria, such as bacteremia, abscess, pneumonia and endocarditis. Amoxicillin can be used to eradicate Helicobacter pylori in addition to upper respiratory tract infections, genitourinary tract infections, skin and soft tissue infections caused by sensitive bacteria. 3. In terms of adverse reactions, the adverse reactions of penicillin are mainly metamorphic reactions, which can be manifested as anaphylactic shock. Hemolytic anemia, etc., generally more serious. And amoxicillin common adverse reactions are diarrhea, nausea, vomiting and so on. 4. In terms of contraindications, penicillin is contraindicated for those who are allergic to penicillin, and amoxicillin is contraindicated for those who are allergic to penicillin or β-lactam agents. Please use the medication under the guidance of a physician, and not blindly use the medication on your own.