It is a penicillin type antibiotic and it does not have sulfa in it. Amoxicillin is used to treat many different types of infection caused by bacteria, such as tonsillitis, bronchitis, pneumonia, gonorrhea, and infections of the ear, nose, throat, skin, or urinary tract. Amoxicillin is a penicillin antibiotic that fights bacteria. It is used to treat many types of infections such as tonsillitis, bronchitis, pneumonia, and others. Amoxicillin is not a sulfa drug. It belongs to the penicillin family of antibiotics, which is a completely separate drug class from sulfonamides. The two groups have different chemical structures, work through different mechanisms, and do not share allergy triggers. No—amoxicillin is not a sulfa antibiotic; it belongs to the penicillin family and functions by disrupting bacterial cell walls rather than inhibiting folic acid synthesis like sulfonamides. There are many non-sulfa antibiotics available as alternatives to sulfa-containing drugs. Two classes that do not contain sulfa are penicillins (such as amoxicillin) and fluoroquinolones (such as Cipro). Amoxicillin is also used to treat tonsillitis and pharyngitis (sore throat). Amoxicillin belongs to the group of medicines known as penicillin antibiotics. It works by killing the bacteria and preventing their growth. However, this medicine will not work for colds, flu, or other virus infections. We can definitively state that Amoxicillin does not contain any sulfa (sulfonamide) components in its drug composition. Its molecular structure is entirely distinct from drugs classified as sulfonamides. Key Takeaway: Amoxicillin is definitively not a sulfa drug; it belongs exclusively to the Penicillin class of antibiotics. The chemical structure of Amoxicillin lacks the specific sulfonamide moiety responsible for sulfa allergies. A Mayo Clinic expert discusses which medicines to avoid if you have a sulfa allergy. When sulfonamides first became available, their uses included treating and preventing bacterial infections. This lasted until penicillin use expanded in the mid-1940s. Today, sulfonamides treat a huge range of conditions, from Type 2 diabetes and high blood pressure to HIV and melanoma.