Like all medications, amoxicillin for injection can cause side effects. Common adverse reactions include gastrointestinal disturbances such as nausea and diarrhea, allergic reactions, and, in rare cases, severe anaphylaxis. Patients with a known allergy to penicillin or cephalosporins should avoid amoxicillin, and its use should be approached with caution in individuals with a history of liver disease or renal impairment.