Doctor-patient verbal interactions face some communication challenges as a result of the sensitive nature of communication in medical contexts. A number of discourse-analytic studies have been carried out on doctor-patient verbal interactions, focusing pertinent pragmatic concerns in medical contexts, but with insufficient attention paid to politeness and its discourse benefits. Therefore, this study explores language use in doctor-patient verbal interactions with the objective of discovering the specific face-threatening acts and politeness maxims employed to enhance diagnostic communication at the University College Hospital, Ibadan, Nigeria. The theoretical framework adopted for this study is a synthesis of Brown and Levinson's politeness theory and Leech's politeness maxims. Fifty tape recordings of doctor-patient recordings were made at the University College Hospital, Ibadan, Nigeria. A total of twenty-five interactions were purposively selected because of their strategic content from the data got at the hospital. The data were then orthographically transcribed and analyzed qualitatively. The various politeness elements perform a number of communicative functions. FTA with redress corrects unwholesome health practices; FTA without redress tactfully obtains medical data for diagnosis; tact maxim expresses compassion; generosity maxim offers advice; sympathy maxim offers guidance, and the ethical positivity tendency opens up talks. Knowledge of these elements of politeness and their discourse functions are therefore crucial to a better comprehension of clinical discourse in Nigeria.