Users of the experimental weight loss drug retatrutide, nicknamed 'the Godzilla shot,' are reporting disturbing mood changes, including a phenomenon described as emotional blunting or anhedonia, the inability to experience pleasure. These accounts have emerged on social media platforms like Reddit and TikTok, where users describe feeling emotionally "dead" or like "emotionless robots".
Retatrutide, which is not yet approved by the Food and Drug Administration, has shown significant weight loss results in clinical trials, with users losing up to a quarter or more of their body weight. However, reports of severe side effects have prompted warnings from regulators about the risks associated with unapproved versions sold online.
User Experiences
One user, 26-year-old Tian Molnar from Australia, shared her experience with the drug. While she noted physical benefits such as appetite suppression and an improved physique, she also reported significant negative changes in her mood and motivation. Molnar described feeling unusually tired, flat, and extremely unmotivated, accompanied by periods of sadness and insecurity. Activities she once enjoyed no longer provided the same happiness or excitement. She emphasized that feeling mentally well was more important than losing a few pounds and advised others experiencing similar effects to stop taking the drug.
Similar sentiments have been shared online, with users describing their souls as having "disappeared" or their emotional state as "genuinely unbearable."
Potential Mechanisms and Scientific Inquiry
These reported mood changes, particularly anhedonia, have been previously noted in some patients using other injectable weight loss medications like semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound). Retatrutide acts by mimicking gut hormones that regulate appetite, targeting GLP-1, GIP, and glucagon receptors. This triple action leads to potent appetite suppression and potentially increased energy expenditure, contributing to its dramatic weight loss effects.
Researchers are investigating whether the drug's influence on the brain's reward system, particularly dopamine pathways, could be responsible for emotional blunting. Dopamine is crucial for motivation and the response to rewarding experiences. While these drugs appear to dampen cravings for food and addictive substances by altering dopamine signaling, scientists theorize that in some individuals, this effect might extend to blunting the pleasure derived from everyday activities, hobbies, or social interactions.
Dr. Mary Sco, a physician specializing in nutrition, suggested that because retatrutide targets more hormonal pathways and has a more powerful effect than other weight-loss drugs, it could potentially lead to more severe anhedonia. The effect may also be dose-related, as seen in a recent report of three women on the highest dose of tirzepatide experiencing emotional flatness that improved upon dose reduction.
Some users have also reported a decreased sex drive, which aligns with the theory that dopamine influences desire and attraction. However, there is also some evidence suggesting that GLP-1 drugs could potentially lower the risk of erectile dysfunction. Interestingly, a small number of users have reported that the emotional flatness has been beneficial, helping them control cravings for less healthy habits like partying, drinking, or excessive sexual activity, allowing them to focus on fitness goals.
Regulatory Status and Safety Warnings
Eli Lilly is conducting Phase 3 trials for retatrutide and plans to seek FDA approval in early 2027. The company has announced plans for a limited early access program for patients with acute clinical needs. Both health officials and Eli Lilly have repeatedly cautioned the public against purchasing products online that claim to be retatrutide, stating that these are often counterfeit and can pose serious health risks due to potential variability in dose, contamination, or incorrect compounds.