Suggest Treatment For Sore Throat And Difficulty In Swallowing

My daughter is 21 years old and ever had amidalitis since little, currently she has the beigining with difficulties for swallow. I have told her to do gargaras with oxigenated water which very much dissaponintng sensation wise, she reacted hating the treatment ina good comfort level, thereafter she continued with salted warm water gargaras which is not a good treatment sensational but less than first oxigenated water. She completed the recommendation with refreshing mint tooth paste. At this moment my wife is confirming her wellness since went she wake up with the throat irritated she was feeling very much bad from past experience since little.girl. Please let me know if this treatment is ok! my wife reported she is feeling much out of the bad wake up feeling. I remember i did have the same condition until 12 years old more less and I want to know if being 21 is normal, let me tell you that the soar throat she had few minutes ago is presented in periods more extended like little. How coudl I solve her throat irritability as I dont present the symptoms since 12 years old more less.