Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain it seems that the symptoms symptoms of severe sneezing,runny nose ,itchy eyes does not seems to be due to Amoxicillin, rather it seems to be due to ALLERGIC RHINITIS and it can be due to causes like allergic reaction to irritants like pollen, animal danders, dust and mites and at times even certain trees and grasses.. I would suggest you to consult an Allergist and get evaluated and a thorough clinical evaluation and investigations like allergic tests like Patch test, RAST test, food challenge test etc can help in diagnosis and treatment can be done accordingly.. The tests will help in ruling out the exact cause of the allergen and once you know the cause of the allergic reaction you can avid exposure to it to prevent allergy attack.. You can also take anti allergics like Levocetrizine, Allegra etc along with steroid nasal sprays to relieve the symptoms.. Do steam inhalations.. You can also be instilled an Immunotherapy that will help in reducing the severity and frequency of allergic attack.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.