The use of ketamine for the management of neuropsychiatric conditions outside traditional clinical settings has rapidly expanded. As a result, there is a critical need to understand diverse real-world patient experiences of ketamine use. We conducted a qualitative content analysis of posts from the r/TherapeuticKetamine subreddit. From 3,302 threads, the 500 highest-engagement threads were analyzed by independent coders across six domains: perceived positive effects, adverse effects, reasons for use, route of administration, polydrug use, and dose amounts. Mood-related concerns were the most reported reason for ketamine use (53%). Users frequently reported positive effects, most often improvements in emotional well-being (65%). Adverse effects were predominantly psychological or mood-related in nature (56%). Notably, 70% of reported doses exceeded 149 mg, suggesting a trend toward higher-dose use. Intravenous administration (40%) and sublingual troches (23%) were the most frequently reported routes. Concurrent use of prescribed psychotropics, cannabis, and psychedelics was also reported. This analysis identified substantial heterogeneity in patient-reported ketamine experiences. The frequent reporting of high-dose use, dose escalation, and polydrug exposure underscores the importance of proactive clinical monitoring and attention to potential drug–drug interactions. Findings should be interpreted with caution, as longitudinal follow-up and clinical verification are not possible through social media data; however, these data provide an unfiltered view of patient experiences that are critical for understanding real-world ketamine use.