Billy jo Jim bob on Instagram: "Amoxicillin is a widely used penicillin antibiotic that treats a variety of bacterial infections, according to Drugs.com and the National Institutes of Health (NIH). Here are some key facts about amoxicillin: Uses Respiratory Tract Infections: Amoxicillin treats upper and lower respiratory infections like sinusitis, tonsillitis, pharyngitis, pneumonia, and bronchitis. Ear, Nose, and Throat Infections: It's often prescribed for middle ear infections (otitis media),