There is not enough evidence to recommend antibiotics as a way to prevent or treat Alzheimer’s disease. One large Taiwanese cohort study found that people hospitalized with Chlamydia pneumoniae pneumonia had a higher risk of Alzheimer’s disease, while those treated with certain antibiotics for at least 15 days had a lower associated risk. However, this type of study shows an association, not proof that antibiotics prevent Alzheimer’s. More research is needed before any treatment recommendations can be made.