Ceftriaxone injection, an antibiotic used to treat bacterial infections, may cause side effects. Common side effects of ceftriaxone injection include pain, swelling, or redness at the injection site, diarrhea, and nausea. Some patients may experience allergic reactions, such as rash, itching, or difficulty breathing. Serious side effects of ceftriaxone injection can include severe stomach pain, bloody stools, or jaundice. Rarely, ceftriaxone injection may lead to kidney issues or blood disorders. Prolonged use of ceftriaxone injection increases the risk of secondary infections. Consult a healthcare provider if side effects of ceftriaxone injection persist or worsen. Always follow medical guidance for safe use.