Surgery and peptides — what to discontinue before, what to restart after

The honest answer to that last part is: often, not much. Peptides are not on most pre-operative checklists. They're not on standard anesthesia intake forms. The pharmacist at the hospital almost certainly doesn't have a reference entry for BPC-157 or ipamorelin. This does not mean they're irrelevant to perioperative care — it means the burden of disclosure and coordination falls on you, because no one in the surgical setting is going to ask the right questions unless you surface the information yourself.

Let's go through what matters and why, starting with the class of compounds that carries the most operationally urgent guidance.

GLP-1 receptor agonists — semaglutide, tirzepatide, and compounded versions of both — are the peptide category with the clearest and most rapidly evolving anesthesia guidance, and the concern is specifically about aspiration. GLP-1 receptor agonists significantly slow gastric emptying. This is part of how they produce satiety and support weight management — food stays in the stomach longer, reducing the speed at which glucose enters circulation and dampening hunger signals. Under general anesthesia, however, a stomach that hasn't properly emptied is a serious problem. When a patient is anesthetized and airway reflexes are suppressed, gastric contents can reflux into the esophagus and be aspirated into the lungs, causing aspiration pneumonia — a complication that ranges from manageable to catastrophic depending on the volume and nature of what's aspirated. The standard pre-operative fasting guidelines — nothing by mouth for eight hours before general anesthesia — are calibrated to normal gastric emptying. In someone whose gastric emptying is significantly slowed by a GLP-1 agonist, those standard fasting windows may not be sufficient to guarantee a empty stomach.

Current guidance from anesthesiology societies, including the American Society of Anesthesiologists, has been evolving over the past two years. The most recent position, which reflects emerging consensus rather than final settled practice, is to hold weekly GLP-1 injections for approximately one week before any procedure requiring general anesthesia or moderate sedation. For daily GLP-1 formulations, the hold is approximately one day. These timelines are almost certainly still being refined as more data accumulates — the guidance has already shifted once and may shift again — which is why confirming the current recommendation with your anesthesiologist before your specific procedure matters more than any general guidance. There may also be situations where the GLP-1 is being used for diabetes management rather than weight loss, and abruptly discontinuing it carries its own glycemic risks that need to be balanced. This is a conversation between you, the provider prescribing the GLP-1, and the anesthesiologist — not a decision to make from a written protocol.

GH-axis peptides — sermorelin, ipamorelin, CJC-1295, tesamorelin — raise a different set of considerations. Growth hormone has effects on fluid balance, and GH-axis stimulation can produce modest sodium and water retention, particularly early in a protocol or at higher doses. Perioperative fluid management is carefully calibrated, and pre-existing fluid shifts from GH-axis activation are a variable the anesthesiologist and surgical team may want to factor in. There's also the question of IGF-1 elevation: elevated IGF-1 can affect wound healing, and the relationship between GH signaling and wound healing is complicated enough that surgical context matters. Some research suggests that adequate IGF-1 supports wound healing — GH signaling drives collagen synthesis and tissue repair, which seems like it should help post-surgical recovery. Other practitioners argue for discontinuing GH-axis compounds in the elective surgery window on the principle of not adding variables to a period where pharmacological stability is valuable. There is no clean randomized controlled trial telling you the right answer here. The standard approach in most centers that work with this population is to discontinue GH-axis peptides one to two weeks before elective surgery, discuss the restart timing with your prescribing provider based on the specific procedure and healing trajectory, and not resume independently.

BPC-157 and TB-500 are popular for their healing and recovery effects, and ironically those same effects are what create the surgical consideration. Both peptides have demonstrated angiogenic properties in research — they promote new blood vessel formation as part of tissue repair. In the context of elective surgery, new blood vessel formation in healing tissue is generally what you want. But in the perioperative window, angiogenic activity in the wrong context — wound beds before surgical closure, vascular anastomoses, complex tissue planes — is less predictable. Surgeons managing elective procedures generally want to perform surgery on tissue that is in its baseline state, not tissue whose vascular biology is being actively modified by an exogenous compound. The practical guidance for most elective procedures is to discontinue BPC-157 and TB-500 at least one to two weeks before surgery. Restart timing is context-dependent: for straightforward soft tissue procedures with expected uncomplicated healing, some prescribing providers consider resumption after initial wound closure is confirmed, typically two to four weeks post-operatively, with the rationale that the angiogenic and tissue-repair effects could support the remodeling phase. For complex surgeries, vascular procedures, or any situation where healing complications have occurred, the restart decision belongs to the surgical team in coordination with your prescribing provider — not on any predetermined timeline.

PT-141 — bremelanotide — has cardiovascular effects that are relevant to surgical safety. It produces a transient increase in blood pressure through melanocortin receptor activation. This effect is well-documented and is part of why PT-141 carries contraindications for cardiovascular disease in its pharmaceutical prescribing information. Before any procedure requiring anesthesia, vasoactive compounds should be disclosed, because anesthesiologists manage blood pressure continuously and unexpected pressor effects complicate that management. PT-141 would typically be discontinued before any surgical procedure, and the hold should be discussed with your anesthesiologist given its pharmacodynamic profile.

The anticoagulation and antiplatelet category extends beyond peptides to include supplements — fish oil, vitamin E at high doses, garlic supplements, gingko, bromelain, turmeric — but within the peptide space, anything with vascular or platelet-relevant activity requires disclosure. The surgical team managing bleeding risk and hemostasis needs to know about compounds that may affect either. This is part of the broader principle: if you're uncertain whether a compound belongs on your pre-operative disclosure, the answer is that it does. The downside of disclosing a compound that turns out to be irrelevant is a three-minute conversation. The downside of not disclosing a compound that turns out to matter is a different kind of problem.

The post-operative restart question is where a lot of people get stuck because there's almost no literature directly addressing it, and the answer is genuinely context-dependent. The general framework: recovery peptides like BPC-157 and TB-500, if the surgical rationale for discontinuation was elective-surgery prudence rather than a specific contraindication, can often be reconsidered after the primary wound has closed and the surgeon confirms uncomplicated initial healing. GH-axis peptides can generally be reconsidered after the acute post-operative period, once the patient is eating normally, glucose and fluid balance have stabilized, and the surgical team has cleared the patient from active monitoring. GLP-1 agonists have specific restart guidance from anesthesiology that is evolving, but in general the same considerations that applied to the pre-operative hold — gastric emptying and its effects on eating and tolerance — apply to when resumption makes sense. Restarting any compound after surgery when post-operative nausea, poor appetite, or delayed healing are present is worth deferring pending clinical evaluation.

The broader point is about communication, and it bears saying plainly: the surgical team does not know what you're taking unless you tell them. Your anesthesiologist, your surgeon, the nursing team managing your pre-operative assessment — none of them will ask about peptides because peptides are not on the standard checklist. You are the only person in the room who has the complete picture of everything entering your body, and the coordination that perioperative safety requires depends on that information being shared explicitly and early. Not on the morning of surgery. Ideally weeks before, at your pre-operative appointment, so there's time to discuss, adjust timelines if needed, and ensure that everyone involved in your care is working from the same information.

The conversation may be unfamiliar for providers who haven't worked with peptide protocols. That's okay. The information you need to give them is simple: the name of each compound, the dose, the frequency, and when you last took it. They can work with that. What they can't work with is not knowing.

Your prescribing provider for the peptides and your surgical team should ideally be in communication before a planned procedure — or at minimum, you should be carrying information between them in both directions. This is how integrated perioperative care works. It is also, in most cases, the patient's responsibility to make it happen, because the systems that would otherwise connect these providers often don't.