In addition, combinations with immune checkpoint inhibitors are being investigated as a strategy to reshape the tumor immune microenvironment and enhance anti-tumor immunity
The molecular basis is multifaceted
Common side effects associated with B12 supplementation include: Local injection site reactions (for intramuscular preparations): Pain, redness, or swelling at the injection site Mild bruising or tenderness Itching localised to the injection area These reactions are usually self-limiting and resolve within 2448 hours

Reported benefits (per available research): Reliably studied for its ability to increase circulating growth hormone (and downstream IGF-1) in both animal models and a human Phase II trial, where it was well tolerated but did not significantly outperform placebo on its primary clinical endpoint Studied in rodent models for effects on bone formation and bone mineral content, including in a glucocorticoid-induced bone-loss model, though this evidence is animal-only and has not been confirmed in controlled human trials Anecdotally and in early/limited research associated with changes in body composition (lean mass, fat mass) and subjective sleep quality, but these claims rely mostly on user reports and small or non-peer-reviewed data rather than robust human clinical trials Known risks and side effects: FDA safety reviewers flagged growth-hormone-secretagogue peptides in this family for potential cardiovascular effects (e.g., increased heart rate, vasodilatory reactions such as flushing and transient hypotension) as part of the rationale for restricting compounding Commonly reported effects include headache, injection-site reactions, and mild fluid retention or bloating tied to growth-hormone-mediated fluid balance changes Because it is sold as an unregulated research chemical outside pharmaceutical manufacturing controls, there is added risk from impurities, mislabeled concentration, and lack of quality assurance, and long-term human safety data remain limited or absent Evidence snapshot: The strongest human evidence is a randomized, double-blind, placebo-controlled Phase II trial (ClinicalTrials.gov NCT00672074) in bowel-resection patients showing ipamorelin was well tolerated but not significantly more effective than placebo for postoperative ileus

However, significant variations in control types (placebo, MET, or intensive lifestyle), concomitant medications, and follow-up windows mean that a robust head-to-head ranking of strategies is still lacking
After the procedure, patients can resume most of their usual daily activities