Discourse devices are the linguistic tools employed to address inherent problems in conversation for health purposes. Doctor-patient verbal interactions face major problems in clinical discourse due to differences in linguistic, sociolinguistic, cultural backgrounds as well as professional and communicative styles of doctors and patients. Therefore, this study explored language use in doctor-patient interactions with the aim of revealing the specific discourse devices employed to enhance diagnostic communication at the University of Ilorin Teaching Hospital (UITH), Ilorin. The theoretical framework adopted for this study is conversation analysis while the conceptual framework is discourse devices. Fifty tape recordings of doctorpatient verbal interactions were made at UITH, Ilorin, from which twenty-five interactions were purposively selected for their strategic content. Thereafter, the data were orthographically transcribed and analysed qualitatively and grammatically, using discourse analysis. The identified discourse devices perform a number of pragmatic functions. Eleven discourse devices were dominant in the data. Doctors employed phatic communion for opening consultations; direct and indirect questions for diagnosis; language switch for explicitness, informativity and mutuality; rapport expressions for cordiality, solidarity and open communication; and religious belief for encouragement and solidarity. Counselling was employed to guide the patients on how best to handle their health. The patients employed answer for response to queries; closing of conversations for terminating consultations; repetition for emphasis; and circumlocution for communicating medical information. Interrogatives were employed for eliciting information. Declaratives were employed for providing information. Language switch, realised by alternate use of English and Yoruba, was employed for clarity. Rapport expressions, realised by social questions, were deployed for ensuring cordiality. 'Sorry' is a culture-bound expression used for empathy and sympathy. Imperatives were employed for giving directives. Some of the observable problems exhibited the possibility of doctors upsetting patients who engaged in injurious health practices. Discourse devices were deployed for addressing specific communication and health challenges during diagnosis at the University of Ilorin Teaching Hospital, Ilorin. Knowledge of the discourse devices and their pragmatic functions, therefore, is important for a better understanding of diagnostic discourse in the Nigerian context.