Direct answer: Blood tests may identify metabolic, kidney, electrolyte, liver, or pancreatic-enzyme changes, but they cannot rule out every GLP-1 complication
A 2025 meta-analysis synthesising multiple discontinuation studies found that after one year off GLP-1s, people regain approximately 60% of weight lost
Back pain is not listed as a common or characteristic adverse effect in the FDA-approved prescribing information for GLP-1 receptor agonists or the dual GIP/GLP-1 agonist tirzepatide
However, this might be consequential to the fatty acid sidechain 38 and not related to NMDA receptor modulation (Extended Data Fig
Thus, even if systemic changes in GLP- 1 levels might not be readily detectable, altered paracrine signaling of GLP-1 could have profound effects on enterochromaffin cells (as mentioned above) (5153), intraepithelial lymphocytes (29) and afferent neurons, in turn impacting intestinal motility, mucosal immune responses and feeding behavior under inflammatory conditions (75)
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