Hi, Yellow patches on tonsils usually suggest pus caused due to pustular tonsillitis. Repeated resurfacing of this could indicate that you have an infection that is resistant to antibiotics you have used like amoxycillin. I would suggest you the following go for a throat swab for culture and sensitivity (this test involves the lab putting in a swab into your throat and slightly rubbing it over your infected tonsils. Then they would test these secretions to determine what bacteria is causing the infection and what antibiotics it is sensitive to) please note that you need to take this test when you have those yellow patches. You could try using some medicated gargle like betadine gargle 2% (depends on what is available ) and follow instructions on the bottle. Since this is just a gargling solution you have lesser tendencies of side effects from repeated antibiotic courses. Start gargling as soon as you start feeling mild soreness and dont wait for symptoms to aggravate. please make sure you dont have any allergies to iodine take protection when you are going out like using protective masks or a simple handkerchief so that you avoid dust inhalation as inhalation is the source of most respiratory infections. Hope this helps. Please get back to me. Take care