Inclusion Criteria:  All patients undergoing isolated tonsillectomy from the age of 5 years to 40 years  Exclusion Criteria:  Known allergy to local anesthetics. Patients using painkillers in the form of opioids fixed before inclusion in the study. People who have a lot of pain often have more pain after known painful stimuli, such as surgery. This is known as the phenomenon of "central sensitization" and "opioid-induced hyperalgesia" and will probably contribute to great heterogeneity within the groups. Because very few people use opioids regularly from those who have an isolated tonsillectomy performed, it can make it difficult to detect any differences between the groups, and the number is far too low to be able to perform stratified analyzes on only these people. Persons weighing less than 10 kg. Persons over the age of 18 who are not competent to give consent. Patients using class Ib antiarrhythmics (lidocaine, mexiletine) due to increased risk of additive toxicity due to structural similarities. (see SPC) Known partial or total heart block that has not had a pacemaker inserted (see SPC) Severe hepatic failure (spontaneous prothrombin time -international normalized ratio (PT-INR)> 2.0). These patients are not offered this type of procedure as day surgery due to the high risk of complications for the surgery itself. Severe renal failure (estimated glomerular filtration rate <15 ml / min / 1.73m2).