This systematic literature review explores the ethical considerations and challenges instructional designers face when integrating artificial intelligence (AI) into the instructional design process for adult learners. Using the Technological Pedagogical Content Knowledge (TPACK) framework to examine the relationship of ethics, pedagogy, and technology in educational contexts, considering the increasing usage of AI. Synthesizing data from peer-reviewed publications, qualitative research, and theoretical papers, the review examines the evolution and application of AI-driven instructional technologies, the ethical issues encountered, and how they affect the educational experiences of adult learners. Crucial topics identified include balancing ethical standards with technological advancements, ensuring learner privacy and data security, and mitigating biases in AI algorithms. The results highlight the need for transparency in AI applications and the ongoing need for professional growth to successfully negotiate the changing ethical environment. This review highlights significant gaps in the literature, including the lack of comprehensive ethical frameworks tailored for AI in adult education, the scarcity of long-term empirical studies on AI's impact, and the need for practical implementation strategies for instructional designers. Addressing these gaps is essential for enhancing the quality and integrity of AI-enhanced adult education. By focusing on stronger ethical frameworks and coordinated efforts among educators, technologists, and policymakers, this review intends to improve the quality and integrity of AI-enhanced adult learning.