Both belong to the same drug class macrolides , so you would also be allergic to Clarithromycin. I suggest you talk to your Dr. first thing tomorrow morning. Clarithromycin, sold under the brand name Biaxin among others, is an antibiotic used to treat various bacterial infections. This includes strep throat, pneumonia, skin infections, H. pylori infection, and Lyme disease, among others. Clarithromycin can be taken by mouth as a pill or liquid. Clarithromycin is used to treat certain bacterial infections, such as pneumonia (a lung infection), bronchitis (infection of the tubes leading to the lungs), and infections of the ears, sinuses, skin, and throat. For information on use of the individual components when dispensed as individual medications outside this combined use for treating Helicobacter pylori, please see the package inserts for each individual product. Clarithromycin oral tablet (Biaxin) is used to prevent and treat certain bacterial infections. Learn about side effects, warnings, dosage, and more. Clarithromycin is a prescription drug used to treat a wide variety of bacterial infections. Learn about side effects, drug interactions, dosages, warnings, and more. Clarithromycin is the generic form of the brand-name prescription drug Biaxin, an antibiotic used to treat bacterial infections. 250 mg PO every 12 hours for 7 to 14 days. Clinical practice guidelines recommend clarithromycin as a monotherapy option in previously healthy outpatients with no risk factors for drug-resistant S. pneumoniae and without therapy in the preceding 3 months. Read all of this leaflet carefully before you start taking this medicine because it contains important information for you. - Keep this leaflet. It is considered safe for people with penicillin allergy to take clarithromycin. However, bear in mind that there still is the possibility of being allergic to clarithromycin.