Yes, if someone has defamed you or your business, a defamation lawyer can assist in drafting a cease and desist letter. This is often the first step in requesting the defamer to stop and retract their false statements.
In addition to a cease and desist letter, there are several other out of court legal avenues and vehicles that can be summoned toward the effort of reputation management. From the demand letter, to the well crafted , to the not yet filed, complaint; OSINT techniques and international laws governing Right to Be Forgotten initiatives, there's more than one way to skin the digital cat.