IntroductionMethadone, a synthetic opioid agonist, has been widely used for the treatment of opioid dependence and chronic pain management for several decades (1). Methadone maintenance treatment (MMT) has proven to be an effective strategy in reducing illicit opioid use, improving patient outcomes, and decreasing the risk of HIV transmission among individuals with opioid use disorders (2). However, despite its therapeutic benefits, methadone can cause significant adverse effects, particularly in opioid-naive individuals or those who consume it recreationally (3).Methadone overdose can lead to severe respiratory depression, cardiac arrhythmias, and death (4). The risk of overdose is particularly high in individuals who are not tolerant to opioids, as they may be more sensitive to the drug’s effects (5). In addition to its well-known respiratory and cardiovascular side effects, methadone can also cause rare neurological and ocular manifestations, such as strabismus (6).Strabismus, a misalignment of the eyes, can occur due to various etiologies, including congenital factors, nerve palsies, and pharmacological agents (7). Opioid-induced strabismus is an uncommon but documented consequence of opioid toxicity, with most cases reported in the context of heroin use (8). The exact mechanism underlying opioid-induced strabismus remains unclear, but it is thought to involve the drug’s effects on the central nervous system and the oculomotor nerve (9).In this case report, we present a rare instance of methadone-induced loss of consciousness and subsequent strabismus in a patient who consumed methadone for the first time. This case underscores the importance of recognizing the potential dangers associated with methadone use, especially in opioid-naive individuals, and the need for healthcare providers to be aware of the uncommon ocular manifestations of opioid toxicity. Prompt identification and appropriate management of methadone overdose and its associated complications can prevent long-term morbidity and mortality (10).