differential diagnosis is strep throat, mononucleosis( ebv ), acute nasopharyngitis (common cold). also consider thrush. More serious diagnoses would be peritonsular cellulitis and peritonsular abscess , the latter would require aspiration by a otolaryngologist or good Ed doc. if left untreated that condition could be life-threatening.

The drug in the picture is known as augmentin in the us and is a broad spectrum antibiotic. it would likely help in a case of strep throat or peritonsular cellulitis. The other processes, not so much.