Hi. What you are experiencing is fairly common. Antibiotics sometimes can take 2 or 3 days to start showing signs of improvement and there can be fluctuating pain relief especially after eating food in the initial days. Inflamed tonsils and throat wall have a good vascular supply and movements of the throat while eating food improves drainage of inflammatory substances into the blood stream and relieves pain. Even though the first few swallowing movements are painful, the subsequent ones get better and there is relief in pain for a few hours. When you are asleep or taking rest, the throat wall has limited movement and allows inflammatory cells to accumulate and increases pain. In addition to the antibiotics, you also may require to take some anti-inflammatory medications and oral antiseptic gargles with Betadine or chlorhexidine (before and after every meal) for about 3 days. If you are on anti-inflammatory medications such as Ibuprofen or Diclofenac, then the waxing and weaning of the pain could also be because of the short lived action of these medications (4-6 hours). I would suggest that you give this another day or two and you should recover back to normal. If your condition remains the same even after 36 hours of antibiotics then see your ENT specialist to evaluate for a more specific antibiotic based on blood work up and culture tests. Try to consume more frequent but smaller meals of soft and bland diet and keep yourself hydrated by drinking plenty of fluids (up to 2 litres/day)