What is the difference between penicillin and amoxicillin? Well, both of them are antibiotics but do they work the same? Which one is better for strep throat, tooth abscess, tonsillitis and other conditions? The cure rates for amoxicillin are similar to those for penicillin V in treatment of strep throat. Some clinical trials have demonstrated that amoxicillin works a bit better [1]. Some clinical trials have demonstrated that amoxicillin works a bit better [1]. We recommend penicillin or amoxicillin for treating strep because they are very effective and safe in those who are not allergic, and there is increasing resistance of strep to the broader. The efficacy and safety of amoxicillin 1 g b.i.d. for 6 days were not statistically different from those of penicillin V 1 MU t.i.d. for 10 days in the treatment of streptococcal tonsillitis in adults. amoxicillin is penicillin based, cephalexin has no penicillin in it at all, they are both used for infections. hope this helps Mark Doctors have presented more evidence that it’s time for long-time antibiotic stalwarts like penicillin and amoxicillin to step aside when it comes to the treatment of strep throat. Doctors give trusted answers on uses, effects, side-effects, and cautions: Dr. Woods on cefdinir vs amoxicillin for strep: It will treat strep. Doctors give trusted answers on uses, effects, side-effects, and cautions: Dr. Woods on cefdinir vs amoxicillin for strep: It will treat strep. Amoxil (amoxicillin) is a good and cheap antibiotic that comes in different forms to treat many types of bacterial infections. Penicillin VK (penicillin) is good at treating strep throat and is cheap, however, it can only be used for certain infections as many bacteria have developed resistance to it. Penicillin or amoxicillin is the antibiotic of choice to treat group A strep pharyngitis. There has never been a report of a clinical isolate of group A strep that is resistant to penicillin. However, resistance to azithromycin and clarithromycin is common in some communities. For patients with a penicillin allergy, recommended regimens include narrow-spectrum cephalosporins (cephalexin. Strep throat is a bacterial infection caused by streptococcus bacteria and is characterized by pus on the tonsils. Strep throat is highly contagious, unless the patient has been on antibiotics for 24 to 48 hours.