Prison inmates’ health security is regularly neglected, even though it is of utmost importance, especially in underdeveloped countries such as Nigeria. The Nigerian correctional system is marked by systemic inadequacies and lack of healthcare infrastructure, among others which continuously increase the health vulnerability of prisoners and jeopardize the rehabilitative aims of incarceration. This study investigates the interplay between rehabilitation deficiencies and health disparities in Nigerian prisons using the experiences of former prisoners and retired healthcare workers. Data were gathered through in-depth interviews with 35 ex-prisoners and 4 retired health practitioners who were sampled using snowball and opportunistic sampling methods. Thematic analysis of the interview data collected revealed several salient issues, such as experiences of delayed or withheld medical care, excessive reliance on generic drugs, mismanagement of chronic and mental illnesses, and widespread disregard for the rights of prisoners to proper healthcare. The findings emphasize the need for swift policy and institution change aimed at ensuring healthcare services among prisons meet human rights standards. Recommendations include boosting the investment of governments in healthcare, guaranteeing more availability of medical staff, and setting up independent oversight systems for monitoring healthcare services in correctional facilities. Resolving these health challenges is crucial to safeguarding the protection of the basic human rights of prisoners and in creating a correctional environment focused on rehabilitation rather than punishment.