Hi Sushil, I can understand your concern. Painful swelling on the upper side of the neck can be due to either throat or tooth infection. Both infections can be controlled with the antibiotics that is prescribed to your father by the doctor. Amoxicillin and Clavulanic Acid combination is a very strong antibiotic that combats almost all head and neck region infections. However, antibiotics do take about 36 to 48 hours to reach the desired level in blood that is needed to decrease the load of bacteria and intensity of infection. Thus, if your father has just started medicines, then he should wait for a day or two to have the effects and finish antibiotic course. For the relief of pain, he can take Acetaminophen 500 mg or Ketorolac 10 mg up to thrice a day. If the swelling and pain still persists after the end of course of antibiotics, then an examination of swelling in relation to neck problems by ENT specialist should be done. In absence of throat or neck problems, a dentist should be consulted to look for focus of infection in the oral cavity. I hope this information helps you. Thank you for choosing HCM. I wish your father feels better soon. Best, Dr. Viraj Shah