Inflammation of the tonsils that has occurred repeatedly. The definition of recurrent may vary somewhat, but the criteria used recently as a measure of severity were five or more episodes of true tonsillitis per year, symptoms recurring for at least a year, and episodes that are disabling and that prevent normal functioning. In some cases recurrent tonsillitis may be related to immunosusceptibility. Evidence exists for a genetic predisposition for recurrent tonsillitis. [https://orcid.org/0000-0002-0736-9199, PMID:15897415]