The study goal is to determine whether oral administration of a probiotic mixture can reduce the incidence of antibiotic-associated diarrhea in patients with community-acquired pneumonia.

Inclusion Criteria:

• Adult patients aged 19 years or older admitted with a diagnosis of community-acquired pneumonia
• Patients eligible for oral medication administration (able to take oral or enteral feeding)

Exclusion Criteria:

• Sepsis patients
• Patients admitted to the intensive care unit (ICU) following endotracheal intubation
• Elderly patients aged 80 years or older
• Pregnant women
• Patients who have diarrhea at the time of admission
• Patients with a history of using probiotics within 3 months prior to admission
• Patients with a history of using laxatives within 1 week prior to admission
• Patients suspected of being in shock (mean arterial pressure < 65 mmHg) at the time of admission