When to Go to ER on Ozempic: Emergency Red Flags vs. Normal Side Effects
Most Ozempic side effects are manageable at home. But certain symptoms signal serious complications requiring emergency evaluation. Learn to distinguish normal nausea from pancreatitis, manageable constipation from bowel obstruction, and mild injection site reactions from anaphylaxis. Knowing when to stay home and when to head to the ER can be life-saving.
Distinguishing Normal Side Effects from True Emergencies
Understanding the spectrum from normal to emergency is essential. Most Ozempic side effects are uncomfortable but self-limited and manageable with home care. Truly serious complications are rare but require immediate hospital evaluation.
Normal side effects (manage at home): Mild-to-moderate nausea (1-4/10 severity, doesn't prevent eating/drinking small amounts), occurring 12-36 hours post-injection, resolving by day 5-6. Mild abdominal cramping (2-4/10 severity, intermittent, improves with bowel movement), occurring usually within first 24 hours post-injection. Mild constipation or loose stool, managed with dietary fiber, hydration, over-the-counter laxatives. Loss of appetite (the intended effect). Mild headache or fatigue. Mild injection site reactions (itching, redness, resolved within 15-20 minutes). Diarrhea lasting 1-3 days then resolving. Low-grade abdominal discomfort manageable with heating pad.
Symptoms requiring urgent provider contact (call nurse line, may need same-day evaluation): Persistent nausea or vomiting lasting >72 hours despite home management. Severe abdominal pain (7+/10) lasting >12 hours (need assessment for pancreatitis or obstruction). Signs of dehydration (dry mouth, very thirsty, urinating minimal amounts, dark urine, dizziness) from inability to maintain hydration due to nausea/vomiting. New thyroid or neck symptoms (lump, swelling, difficulty swallowing). Unusual allergic symptoms localized to injection site (significant swelling, spreading rash). Drastically reduced urine output over days. Severe constipation lasting >5-7 days unresponsive to laxatives.
Symptoms requiring ER evaluation (call 911 or go immediately): Severe, persistent abdominal pain especially radiating to back (possible pancreatitis), sudden severe pain in right upper abdomen (possible gallbladder emergency), inability to keep any fluids down for >24 hours with signs of severe dehydration, signs of bowel obstruction (severe bloating/distension, complete inability to pass stool/gas for >24 hours, persistent vomiting), signs of allergic reaction (difficulty breathing, throat swelling, widespread hives, facial swelling, rapid heartbeat), signs of kidney injury (drastically reduced or no urine output, dark urine, severe back pain, shortness of breath, confusion), chest pain or severe shortness of breath, signs of infection/sepsis (high fever 103°F+, confusion, rapid heartbeat, severe weakness).
Pancreatitis Red Flags: The Serious Abdominal Emergency
Acute pancreatitis is among the most serious complications of GLP-1 medications. While rare, it's critical to recognize because early treatment prevents severe outcomes and potential mortality.
What is pancreatitis and why is it concerning? Pancreatitis is inflammation of the pancreas, caused by GLP-1 medications through mechanisms including altered bile flow and increased cholesterol saturation in bile, promoting gallstone formation and subsequent obstruction and pancreatic inflammation. Severe acute pancreatitis can progress to necrotizing pancreatitis (pancreatic tissue death), organ failure, and death if not treated promptly.
Recognizing acute pancreatitis symptoms: The hallmark symptom is severe epigastric (upper middle abdomen) pain, often radiating to the back. This back radiation is key—it distinguishes pancreatitis from simple GI upset. Characteristics:
Severe pain intensity (typically 7-10/10 on pain scale, described as severe, constant aching/pressure in upper abdomen). Patients with pancreatitis pain cannot lie flat or move comfortably; they often bend double or assume fetal position. The pain doesn't improve with typical home remedies (heating pad, antacids) and often worsens.
Radiation pattern: pain often radiates straight through to the back between shoulder blades or lower back. This back radiation is highly specific to pancreatitis and distinguishes it from other abdominal emergencies.
Persistent nature: pain is constant, not intermittent cramping. It's present most of the time, unlike gallstone colic (which comes in waves).
Associated symptoms: persistent nausea/vomiting (often severe and repeated), fever (102-104°F), tachycardia (heart rate >100 bpm), possible abdominal swelling/tenderness on palpation.
Timing: symptoms typically develop within 24-72 hours of GLP-1 dose escalation or within weeks of starting medication, though can occur anytime during treatment.
What happens in the ER: ER physicians will order serum lipase and amylase (pancreatic enzymes). Pancreatitis typically shows markedly elevated pancreatic enzymes (amylase or lipase >3 times upper normal limit). They'll also order liver enzymes (often elevated), bilirubin (elevated if biliary involvement), glucose (often elevated), electrolytes (often abnormal). Abdominal imaging (CT scan) may be performed to assess severity and complications. Treatment focuses on supportive care: IV fluids (often 250-500 mL/hour), NPO status (nothing by mouth), pain management (opioids often necessary), anti-nausea medications, monitoring for complications. Most uncomplicated pancreatitis resolves within 3-7 days with supportive care. Severe or necrotizing pancreatitis may require intensive care unit admission, prolonged hospitalization, or surgical intervention.
Prevention and risk reduction: Pancreatitis risk is approximately 1-10 per 1,000-10,000 patients on GLP-1 medications. Risk factors include prior pancreatitis history, gallstone disease, elevated triglycerides, and possibly rapid dose escalation. If you have prior pancreatitis, discuss with provider—GLP-1 medications may be contraindicated. If you develop severe upper abdominal pain, don't wait to schedule office visit; seek ER evaluation immediately.
Gallbladder Emergencies: When Biliary Colic Becomes Critical
GLP-1 medications increase gallstone formation by 20-50% through effects on bile composition and gallbladder motility. While most gallstones are asymptomatic, they can cause acute emergencies requiring hospitalization.
GLP-1 effect on gallbladder: GLP-1 agonists reduce gallbladder contractility (squeezing ability), leading to bile stasis (accumulation). Reduced bile flow increases cholesterol saturation and promotes gallstone precipitation. Simultaneously, GLP-1 medications often accompany rapid weight loss, which itself increases gallstone formation. The combination makes GLP-1 users 2-3 times more likely to develop gallstones compared to weight-stable population.
Gallstone complications requiring ER evaluation:
Biliary colic (uncomplicated gallstone pain): Sudden onset severe pain in right upper quadrant (upper right belly), often radiating to right shoulder or back, lasting 30 minutes to several hours. Pain is typically 7-9/10 severity, constant (not cramping), and may be accompanied by nausea. Biliary colic is painful but not immediately dangerous (gallbladder isn't inflamed, bile isn't backed up). However, because colic is unpredictable and may signal developing complication, go to ER for evaluation if experiencing sudden severe right upper quadrant pain radiating to shoulder/back. ER will perform ultrasound, confirm gallstones, assess for complications, and discuss management.
Acute cholecystitis (gallbladder inflammation): Colic pain that persists >6 hours and is accompanied by fever, persistent vomiting, possible jaundice (yellowing). Ultrasound shows gallstones + signs of inflammation (thickened gallbladder wall, pericholecystic fluid). This is an emergency requiring hospitalization, IV antibiotics, and possibly surgery. Go to ER immediately if experiencing prolonged right upper quadrant pain with fever.
Choledocholithiasis (common bile duct obstruction): Gallstone migrates into common bile duct, obstructing bile flow and backing up into liver and bloodstream. Symptoms: persistent pain, jaundice (yellowing of skin/eyes, dark urine, pale stools, itching from bile salts on skin), fever. This is an emergency requiring hospitalization, possible ERCP (endoscopic retrograde cholangiopancreatography—procedure to retrieve stone from bile duct). Go to ER immediately if experiencing right upper quadrant pain with jaundice.
Gallstone-induced pancreatitis: Gallstone migrates into pancreatic duct, causing pancreatitis (see pancreatitis section). Symptoms overlap with acute pancreatitis (see above). This is a surgical emergency. Go to ER immediately if experiencing severe pain, especially with jaundice or fever.
ER evaluation and management: ER will perform right upper quadrant ultrasound (best imaging for gallstones and inflammation). If gallstones identified with signs of inflammation or obstruction, you'll be admitted for hospitalization. Treatment may include: IV fluids, NPO status, IV antibiotics (if cholecystitis suspected), pain management, urgent ERCP if bile duct obstruction, or surgical intervention if gallbladder perforation.
Prevention: Not all gallstones are preventable, but risk reduction strategies include: maintaining adequate fat intake (30-40% of calories; very low-fat diets increase stone risk), staying hydrated, avoiding rapid weight loss (>3 pounds weekly if possible, though this is often unavoidable on GLP-1s), ursodeoxycholic acid supplementation (250-500 mg twice-three times daily during rapid weight loss) may modestly reduce gallstone formation though evidence is mixed.
Severe Dehydration from Vomiting and Diarrhea: When Fluid Loss Becomes an Emergency
Nausea, vomiting, and diarrhea from GLP-1 medications are common but usually manageable. However, severe fluid loss can lead to dangerous dehydration requiring emergency IV fluid repletion.
How dehydration develops on GLP-1s: Ozempic causes nausea/vomiting through GLP-1 receptor activation in the chemoreceptor trigger zone. Persistent vomiting prevents oral fluid and nutrient intake. Simultaneously, GLP-1 medications slow gastric emptying, meaning liquid stays in stomach longer before absorption, worsening vomiting before fluids can be absorbed. Dehydration compounds side effects: vomiting worsens with dehydration (dehydration itself triggers nausea), electrolyte losses from vomiting/diarrhea worsen nausea and fatigue. A vicious cycle can develop: nausea → vomiting → dehydration → worse nausea → more vomiting.
Recognizing severe dehydration:
Mild dehydration (manage at home): dry mouth, mild thirst, urine somewhat darker than usual. Able to tolerate small frequent sips of water/electrolyte solution.
Moderate dehydration (contact provider urgently): significant thirst, dry mouth and dry skin, dizziness when standing (orthostatic hypotension), urine dark amber, decreased urine output, fatigue. May need IV fluids if oral repletion insufficient.
Severe dehydration (ER emergency): intense thirst, dry mucous membranes, skin tenting (pinched skin takes >2 seconds to return flat), dizziness/fainting, confusion or altered mental status, rapid or weak pulse, minimal/no urine output (<200 mL daily), low blood pressure. May progress to shock (extreme weakness, nearly unconscious state).
What ER does: Labs will show elevated creatinine/BUN (kidney function impairment from dehydration), elevated electrolytes (sodium, potassium), possible acidosis. IV fluids (normal saline typically 500-1,000 mL/hour) are administered until rehydration achieved and lab values normalize. Electrolytes are repleted (potassium, bicarbonate) as needed. Anti-nausea medications (ondansetron, promethazine) are given IV to stop vomiting and allow oral hydration resumption.
Prevention: Maintain proactive hydration (8-10+ cups water daily). If experiencing nausea limiting fluid intake, take ondansetron (Zofran) 4-8 mg every 6-8 hours to reduce nausea and allow oral hydration. Sip electrolyte solutions (coconut water, oral rehydration salts, Pedialyte) rather than water alone to maintain electrolytes. If unable to tolerate any fluids despite anti-nausea medication, contact provider urgently—may need IV hydration outpatient or warrant ER evaluation.
Allergic Reactions and Anaphylaxis: Recognizing Severe Immune Response
True allergic reactions to semaglutide are rare but are medical emergencies when they occur. Distinguishing minor injection site reactions from serious allergic reactions is critical.
Minor allergic/inflammatory reactions (manage at home or call provider): Injection site itching or mild swelling (appearing 10-20 minutes post-injection, resolving within 20-30 minutes). Mild localized rash at injection site. Slight facial flushing. These are common and usually resolve spontaneously. If persistent, topical antihistamine (hydrocortisone cream) may help. Antihistamine pretreatment (cetirizine 10 mg or fexofenadine 180 mg taken 30 minutes before injection) prevents recurrence.
Serious allergic reaction/anaphylaxis (ER emergency—call 911):
Respiratory symptoms: Difficulty breathing or shortness of breath at rest, wheezing, stridor (high-pitched breathing sound), chest tightness, persistent cough, throat tightness sensation.
Airway/throat symptoms: Throat swelling or sensation of throat closing, tongue swelling (glossal edema), lip swelling (angioedema), drooling or difficulty swallowing, voice changes (hoarseness).
Cardiovascular symptoms: Rapid heartbeat (tachycardia >120 bpm), palpitations (feeling heart racing/skipping), chest pain, severe dizziness or fainting, very low blood pressure.
Skin reactions: Widespread hives/rash covering large body areas (>10% of body surface), severe itching, flushing, facial swelling.
GI symptoms: Severe nausea/vomiting, abdominal cramping/pain in context of other allergic symptoms.
What makes anaphylaxis an emergency: Anaphylaxis progresses rapidly (symptoms develop within minutes to 1 hour of exposure). Airway compromise can develop suddenly and become life-threatening within minutes. Hypotension from anaphylaxis can progress to shock, leading to loss of consciousness and death if untreated. Biphasic reactions can occur: initial symptoms resolve partially, then recur hours later more severely.
Immediate action for suspected anaphylaxis: Call 911 or go to ER immediately. Do NOT wait. Do not try to manage at home. Describe symptoms to emergency responders. If available, lie flat with legs elevated (improves blood flow to vital organs). If you have epinephrine auto-injector (EpiPen), use it while awaiting ambulance (0.3-0.5 mg IM into outer thigh). ER will treat with: epinephrine 0.3-0.5 mg IM (first-line treatment), IV access and fluid administration, continuous monitoring, IV antihistamines (diphenhydramine 25-50 mg IV), IV corticosteroids (methylprednisolone or dexamethasone), observation 4-24 hours (monitor for biphasic reaction).
After anaphylaxis: You'll likely be prescribed epinephrine auto-injector (EpiPen) for future use if needed. Semaglutide will be contraindicated (true IgE-mediated allergy). Alternative GLP-1 agonists (liraglutide, dulaglutide, tirzepatide) may have cross-reactivity risk but may be tolerated. Different medication classes (orlistat, phentermine) might be alternatives. Discuss with allergist and prescriber.
Kidney Injury Red Flags: Recognizing Acute Kidney Dysfunction
GLP-1 medications can precipitate acute kidney injury, particularly in dehydrated patients. Early recognition and hydration may prevent severe dysfunction.
How GLP-1s affect kidneys: Mechanistically, GLP-1 medications increase natriuresis (sodium/water excretion in urine), promoting diuretic-like effects. In well-hydrated individuals this is benign. However, in dehydrated patients (from vomiting, diarrhea, or inadequate intake), GLP-1-mediated fluid loss superimposed on existing dehydration can cause acute tubular necrosis and acute kidney injury. Particularly vulnerable: patients taking diuretics (blood pressure medications), patients with baseline kidney disease, patients over age 75, patients with diabetes.
Recognizing acute kidney injury:
Severe reduction in urine output: Producing <300-400 mL daily (dark, concentrated urine) versus normal 1-2 liters. Some patients produce near-zero urine (<100 mL) over 8-12 hours—this is severe and warrants ER evaluation.
Dark urine: Tea-colored or cola-colored urine from concentrated waste products.
Fluid retention symptoms: Leg/foot swelling (pitting edema), weight gain of 2-5+ pounds over days, shortness of breath at rest (fluid in lungs), abdominal bloating.
Systemic symptoms: Fatigue, weakness, poor appetite, nausea/vomiting, confusion or altered mental status (uremia from accumulating waste), muscle weakness or cramps (from electrolyte abnormalities).
Lab findings (detected in hospital): Creatinine elevated significantly (50%+ above baseline), BUN elevated, urinalysis may show protein/blood, potassium elevated (hyperkalemia), metabolic acidosis (low pH).
When to go to ER: Go immediately if experiencing: drastically reduced or absent urine output (<100-200 mL over 8-12 hours) combined with dark urine, or significant leg swelling and shortness of breath, or confusion/altered mental status. Call provider urgently (may need same-day labs) if noticing gradual decline in urine output over days or darkening of urine alone—lab assessment warranted but may not need ER.
ER management: Labs including creatinine, BUN, electrolytes, and urinalysis. IV fluids administered carefully to rehydrate while monitoring kidney response. Electrolyte repletion if needed (particularly potassium if hyperkalemic). Monitoring of urine output and repeat labs. If kidney injury severe or not improving with hydration, nephrology consultation. Ozempic typically held during acute kidney injury; restarting discussed only after kidney function recovers.
Prevention: Maintain excellent hydration (8-10+ cups daily, more if exercise or hot weather). If experiencing vomiting/diarrhea limiting fluid intake, use anti-nausea/antimotility medications to restore ability to drink fluids. If on diuretics (blood pressure medications), discuss with provider—may need adjustment if starting GLP-1. Baseline kidney function should be assessed before starting GLP-1 (creatinine, BUN); if baseline kidney disease exists, discuss with provider about safety and monitoring needs.
Thyroid Lumps and Neck Symptoms: When to Worry About Thyroid Cancer Risk
GLP-1 medications carry a Black Box warning for thyroid C-cell tumors (medullary thyroid cancer risk). While no confirmed human cases of thyroid cancer from GLP-1s have occurred in clinical trials, the theoretical risk warrants vigilance for neck symptoms.
Understanding the thyroid cancer risk: The Black Box warning derives from animal studies: rats given high-dose GLP-1 agonists developed medullary thyroid cancers (tumors arising from calcitonin-producing C cells). Mechanistically, GLP-1 receptors are expressed on C cells and may stimulate proliferation at high doses. However, human evidence suggests lower risk: clinical trials of GLP-1s (involving thousands of patients) haven't detected increased thyroid cancers. The theoretical risk prompted FDA Black Box warning out of caution, not confirmed harm.
GLP-1s are contraindicated if you have: personal history of medullary thyroid cancer, or multiple endocrine neoplasia syndrome type 2 (MEN2). These populations should not use GLP-1 medications.
Thyroid symptoms warranting evaluation:
Non-emergency (urgent provider evaluation): Neck lump or mass (felt by you or noted by others), persistent neck swelling, difficulty swallowing (not just once but recurring), persistent hoarseness or voice changes lasting >2 weeks, neck pain or tenderness, enlarged lymph nodes (felt as bumps in neck/jaw area).
What to do: Call your provider urgently (same-day or next-day appointment). Describe lump/swelling location, size, firmness, pain, any growth over days/weeks. Provider will likely examine neck and order thyroid ultrasound. Thyroid ultrasound is simple, painless imaging showing thyroid size, texture, and any nodules. If nodule present, ultrasound characterizes it (benign vs. suspicious features). Most thyroid nodules are benign (colloid cysts, adenomas); suspicious features (hypoechoic, irregular borders, calcifications, rapid growth) warrant fine needle aspiration biopsy to assess for malignancy.
Emergency thyroid symptoms (go to ER): Severe neck swelling with difficulty breathing or stridor, inability to swallow saliva, severe neck pain with fever (possible thyroiditis/infection), signs of infection (fever, severe swelling, purulent drainage).
Bottom line: If you notice neck lump or swelling while on GLP-1 medications, don't panic—most thyroid nodules are benign. But do get it evaluated by your provider. Early evaluation is far easier than delayed diagnosis. If high-risk category (personal history medullary cancer or MEN2), discuss with provider before starting GLP-1—likely contraindicated.
Bowel Obstruction: When Constipation Becomes a Surgical Emergency
Bowel obstruction is a rare but serious complication of GLP-1 medications, estimated at 0.1-1% of patients. Recognizing progression from manageable constipation to surgical emergency is critical.
How GLP-1s contribute to obstruction: GLP-1 medications slow gastric emptying and reduce intestinal motility. Simultaneously, reduced appetite leads to lower overall food and fiber intake, reducing intestinal bulk. The combination can lead to severe constipation in susceptible patients. Additionally, rapid weight loss on GLP-1s increases risk of internal adhesions (scar tissue in abdomen) from previous abdominal surgeries or other causes; these adhesions can kink bowel and cause obstruction. Dehydration from vomiting/diarrhea also increases obstruction risk by reducing stool water content and intestinal fluid secretion.
Progression from constipation to obstruction:
Simple constipation (manageable): Infrequent stool passage (every 2-3 days), able to pass stool when straining, sometimes hard stools, mild abdominal discomfort. Manage with fiber, fluids, stool softeners, osmotic laxatives.
Severe constipation (urgent provider contact): No stool for 3-5 days despite normal appetite/eating, severe straining causing pain or bleeding, hard stool or incomplete stool passage, abdominal bloating/discomfort, possible nausea. Call provider; may warrant manual disimpaction, stronger laxatives, or assessment for obstruction.
Partial obstruction (ER evaluation): No stool for 5+ days, inability to pass any gas, severe abdominal distension (visibly swollen belly), severe cramping pain, nausea/vomiting. Partial obstruction may resolve with aggressive bowel regimen (high-dose osmotic laxatives, enema) or may progress to complete obstruction. Imaging (abdominal CT) usually needed to assess. ER evaluation warranted.
Complete bowel obstruction (surgical emergency): Complete inability to pass stool or gas for >24 hours, severe pain and distension, persistent vomiting (especially if fecal-smelling, suggesting backed-up bowel contents), severe electrolyte abnormalities and shock if prolonged (low blood pressure, confusion, weak pulse). This is a surgical emergency requiring immediate ER evaluation and likely operative intervention.
Why complete obstruction is dangerous: Prolonged obstruction leads to: bacterial translocation (bacteria crossing compromised bowel wall into bloodstream, causing sepsis), bowel ischemia (tissue death from loss of blood supply), bowel perforation (rupture into abdomen, massive infection), multi-organ failure and death if untreated beyond 24-48 hours.
ER evaluation and treatment: Abdominal imaging (CT scan with contrast) shows bowel obstruction with dilated loops and transition point (where obstruction occurs). Labs show electrolyte abnormalities, elevated white blood cell count. Initial treatment: NPO status (nothing by mouth), IV fluids and electrolyte repletion, nasogastric tube (tube through nose to stomach to decompress bowel), pain management. If partial obstruction resolves with supportive care (70-80% of partial obstructions), no surgery needed. If complete obstruction or failure to improve within 24-48 hours, surgery required to relieve obstruction (adhesiolysis if adhesions, or bowel resection if necrotic bowel).
Prevention: Constipation management on GLP-1s is proactive. High fiber intake (25-35 grams daily) through vegetables, fruits, legumes, whole grains. Excellent hydration (8-10+ cups daily). Stool softener use from the start (docusate 100-200 mg daily) if constipation develops. Osmotic laxative (polyethylene glycol, miralax) if needed. Regular movement and exercise stimulates bowel motility. If developing constipation not responding to these measures within 5 days, contact provider—may need stronger intervention or Ozempic dose adjustment rather than allowing obstruction to develop.
Always Err on the Side of Caution:
If you're unsure whether symptoms warrant ER evaluation, it's better to go or call your provider urgently than to wait. Serious complications can deteriorate rapidly. Your provider or ER can quickly determine if evaluation is needed. Never worry that you're "overreacting"—emergency evaluation is designed to assess exactly these uncertain situations.
How to Communicate Your Ozempic Use to ER Physicians
Accurate communication about your medication and timeline helps ER physicians make correct diagnoses and avoid potentially harmful drug interactions or missed diagnoses.
Critical information to provide:
Medication name and dose: "I'm taking semaglutide (or Ozempic/Wegovy), at 1.0 mg weekly" (specify which, as Ozempic is for diabetes, Wegovy for weight loss, though they're identical—clarifying avoids provider confusion).
Last injection date and time: "I injected on Monday at 7 PM" (helps ER assess recent exposure).
Injection frequency: "I inject weekly" (most important to specify; some ER physicians may be unfamiliar with GLP-1 dosing).
Duration of use: "I've been on this medication for 3 months" or "I just restarted after stopping for 2 months."
Recent dose changes: "I escalated to 1.0 mg two weeks ago" (important for assessment of whether symptoms are dose-related).
Relevant medical history: prior pancreatitis, gallstones, kidney disease, diabetes, thyroid disease (relevant to differential diagnosis of current symptoms).
Allergies to GLP-1 or similar medications, if any.
Symptom description: Be specific about location, severity, timing, and associated symptoms. Example: "I have severe pain in my upper belly (epigastrium) that radiates to my back, started this morning, 8/10 severity, constant, accompanied by vomiting. I last ate breakfast and have been vomiting since noon." This level of detail helps ER rapidly narrow differential diagnosis.
Medication list: Provide complete medication list (all medications, supplements, herbal products you take). GLP-1s can interact with insulin/sulfonylureas (increasing hypoglycemia risk) and potentially with certain blood pressure medications if diuretics involved.
Mention if you took more than prescribed: If you double-dosed accidentally or intentionally escalated faster than prescribed, disclose this. It guides ER assessment and helps them focus on overdose-related complications rather than investigating other causes unnecessarily.
Frequently Asked Questions
Severe nausea alone is rarely an emergency but requires assessment. The distinction: mild-to-moderate nausea (uncomfortable but can tolerate small sips of water, doesn't prevent sleep) is expected side effect, managed at home with anti-nausea medication, ginger, bland foods. Severe nausea becomes concerning when: you cannot keep any fluids down and are becoming dehydrated (dry mouth, dark urine, dizziness, weakness), or nausea persists more than 48-72 hours without improvement (unusual—most nausea improves by day 4-5). Go to ER if you've vomited repeatedly (5+ times in 12 hours), cannot tolerate any food/fluids, or show signs of severe dehydration (confusion, severe dizziness, fainting). Otherwise, manage with anti-nausea medications (ondansetron 4-8 mg) and hydration for 24-48 hours at home; call your provider if nausea persists beyond 72 hours. The critical distinction: dehydration from nausea is the emergency, not nausea itself.
Pancreatitis is a serious complication of GLP-1 medications (though rare, approximately 1 per 1,000-10,000 patients). Red flags for acute pancreatitis: Severe abdominal pain in epigastrium (upper middle abdomen, below ribs) or radiating to the back (this back radiation is key—distinguishes pancreatitis pain from simple GI upset). Pain severity is typically 7/10 or higher (far exceeds typical GLP-1 nausea/cramping pain). Pain is persistent (not intermittent cramping but constant aching/pressure). Associated symptoms: nausea/vomiting, fever, rapid heartbeat, abdominal tenderness on palpation. Laboratory findings (seen in hospital): elevated pancreatic enzymes (amylase, lipase 3+ times upper normal limit), elevated liver enzymes, elevated bilirubin (yellowish skin/eyes suggesting jaundice). Go to ER immediately if you experience severe epigastric pain radiating to back, especially if accompanied by persistent vomiting. Do NOT wait—early treatment (IV fluids, NPO status, pain management) prevents severe complications. Call 911 or have someone drive you immediately. Tell ER physicians you're on Ozempic/GLP-1 medication as they consider pancreatitis in differential diagnosis.
Most GLP-1 abdominal discomfort is manageable cramping or gas. Emergency vs. home-manageable abdominal pain: NORMAL cramping: mild-moderate pain (3-4/10 severity), intermittent (comes and goes), improves with bowel movement/gas passage, occurs usually within first 12-24 hours post-injection, associated with nausea or loose stool. Manage at home: heat pad, anti-spasm medication (dicyclomine 10-20 mg), bowel regularity (stool softener if needed), clear liquids. EMERGENCY pain: severe pain (7+/10 severity), constant rather than intermittent, unrelated to bowel movements, persists >6-12 hours, radiates to back or shoulder, accompanied by fever/chills, causes you to double over or prevents normal activity. ALSO emergency: pain accompanied by signs of bowel obstruction (inability to pass gas or stool for 24+ hours despite urgency, abdominal bloating/distension, vomiting), or peritonitis (severe tenderness when touching abdomen, guarding/rigidity). Go to ER if pain exceeds 6/10 severity, persists >12 hours, or is accompanied by concerning systemic symptoms. Call your provider for pain 4-5/10 that's manageable; discuss anti-spasm medication or whether dose reduction is warranted.
GLP-1 medications increase gallstone formation risk (mechanistically through reduced bile flow and increased cholesterol saturation). Gallstone-related symptoms requiring ER: Biliary colic (severe right upper quadrant or epigastric pain, often radiating to right shoulder/back, episodic lasting 30 minutes to several hours). Acute cholecystitis (biliary colic + fever, elevated white blood cell count on lab, possible jaundice). Pancreatitis from gallstone obstruction (see pancreatitis red flags above). Choledocholithiasis (common bile duct obstruction causing jaundice, dark urine, pale stools). Emergency features: Right upper quadrant pain 7+/10 severity, pain radiating to right shoulder or back, fever, jaundice (yellowing of skin/eyes), persistent vomiting, dark urine or pale stools, abdominal tenderness/guarding on palpation. NON-EMERGENCY right upper quadrant discomfort: mild pain 2-4/10, brief episodes (minutes), no fever/jaundice, able to eat and function normally. Call provider if experiencing occasional mild right upper quadrant discomfort (possible gas, consider ultrasound evaluation). Go to ER if experiencing severe right upper quadrant pain 7+/10 lasting >30 minutes, especially if fever or jaundice present. ER will perform ultrasound/imaging; if gallstones identified and inflammation present, may require hospitalization or surgical intervention.
GLP-1 medications can cause acute kidney injury, particularly in dehydrated patients. Kidney injury red flags: Drastically reduced urine output (producing 200-300 mL daily or less versus your normal 1-2 liters), dark or tea-colored urine, urinary discomfort/burning (UTI may precede kidney issues), lower back/flank pain (kidney area), swelling in legs/feet (edema from fluid retention), shortness of breath at rest (sign of severe fluid overload), confusion or altered mental status (uremia from kidney dysfunction), severe nausea/vomiting in setting of reduced urine output. Laboratory findings: creatinine elevated 50%+ above baseline, BUN elevated, potassium elevated (hyperkalemia), metabolic acidosis (low pH on lab). Go to ER if experiencing drastically reduced urine output (<300 mL daily) combined with dark urine, or if output drops to near-zero (<100 mL) over 8-12 hours. Contact provider urgently (call nurse line) if noticing gradual decline in urine output over days or darkening of urine without other symptoms—may need urgent labs but not necessarily ER. Prevent kidney injury by maintaining excellent hydration (8-10 cups water daily minimum, more if exercising or in hot weather). If experiencing nausea/vomiting limiting fluid intake, discuss with provider—may need anti-nausea medication or dose adjustment to maintain hydration.
True allergic reactions to semaglutide are rare (anaphylaxis <0.1% of patients) but are emergencies requiring immediate ER evaluation. Allergic reaction red flags: Anaphylaxis symptoms: difficulty breathing or shortness of breath, throat tightness or throat closing (stridor), facial/lip/tongue swelling (angioedema), rapid or irregular heartbeat, hypotension (dizziness, fainting), skin reactions (hives/rash covering large body areas, itching), nausea/vomiting in context of other allergic symptoms. Minor allergic symptoms (not emergency but warrant provider notification): localized itching at injection site (expected, usually resolves in 10-15 minutes), mild rash at injection site, itching elsewhere on body, mild facial flushing. EMERGENCY allergic reaction: Go to ER or call 911 immediately if experiencing any combination of: difficulty breathing, throat swelling, widespread hives/rash, facial/lip swelling, rapid heartbeat, dizziness, or fainting in context of recent injection (within 1 hour). The ER will treat anaphylaxis with epinephrine injection, IV antihistamines, and corticosteroids. DO NOT try to manage anaphylaxis at home—it can rapidly deteriorate and become life-threatening. Minor local allergic symptoms usually resolve on their own; inform your provider who may recommend antihistamine pretreatment before future injections or switching to alternative GLP-1 if reaction recurring. True IgE-mediated allergy to semaglutide may require switching to alternative GLP-1 agonist (though cross-reactivity possible).
Thyroid lumps or neck swelling warrant urgent evaluation but are not emergencies requiring ER visit unless accompanied by emergency symptoms (difficulty breathing/swallowing, severe airway obstruction). GLP-1 medications carry Black Box warning for thyroid C-cell tumors (medullary thyroid cancer risk from animal studies; no confirmed human cases in clinical trials, but theoretical risk). Red flags: Neck lump or mass (self-felt or noted by others), persistent difficulty swallowing, persistent voice changes (hoarseness lasting >2 weeks), neck pain or swelling, enlarged lymph nodes. Non-emergency approach: call your provider urgently (same day/next day) if noting neck lump or swelling. Provide description: location (front-center vs. side), size, firmness, pain, if growing. Provider will likely arrange thyroid ultrasound, which typically occurs within 3-7 days. Ultrasound will determine if nodule present and characteristics. Most thyroid nodules are benign; suspicious features (hypoechoic, irregular borders, calcifications) warrant biopsy. Emergency approach: Go to ER if neck swelling accompanied by: difficulty breathing or stridor (sign of airway compromise), difficulty swallowing saliva, severe neck pain, fever (sign of infection/thyroiditis). These symptoms suggest thyroiditis or airway emergency needing immediate intervention beyond routine biopsy. If you have prior history of medullary thyroid cancer or multiple endocrine neoplasia (MEN2), Ozempic is contraindicated; don't use it and discuss alternatives with provider.
Bowel obstruction is a rare complication of GLP-1 medications (estimated 0.1-1% of patients) but is a surgical emergency. Bowel obstruction red flags: Complete inability to pass stool or gas (no bowel movement >24 hours despite urge, no intestinal gas passage) accompanied by: severe abdominal pain and cramping, progressive abdominal distension/bloating (belly significantly swollen), persistent vomiting (especially if vomit is fecal-smelling), constipation progressing to inability to pass flatus. Laboratory findings (detected in hospital): imaging shows dilated bowel loops with transition point, elevated white blood count, electrolyte derangements, possible fever. This is surgical emergency because: prolonged obstruction leads to bowel ischemia and perforation, peritonitis, sepsis, multi-organ failure if untreated. Go to ER immediately if experiencing: no stool or gas for >24 hours, severe abdominal cramping, progressive bloating, persistent vomiting in context of constipation. ER will perform abdominal CT imaging to confirm obstruction and determine site. May require hospitalization, NPO status, IV fluids, and possibly surgical intervention (adhesiolysis if adhesions causing obstruction, or bowel resection if significant damage). Prevention: maintain excellent fiber intake (25-35 grams daily), adequate hydration (8+ cups water), regular movement/exercise to stimulate bowel motility. If developing constipation on Ozempic, use stool softener (docusate) or osmotic laxative (polyethylene glycol) to prevent progression to obstruction.
Communicating your medication accurately helps ER physicians make correct diagnoses and avoid harmful drug interactions. Information to provide: Medication name (semaglutide, Ozempic, Wegovy, or compounded semaglutide—specify which), dose (e.g., 1.0 mg weekly), injection frequency (weekly), date of last injection (specific day/time helps assess recent exposure), indication (weight loss vs. diabetes), how long you've been on medication (days/weeks/months), and any recent dose changes (if within 1-2 weeks). Relevant history to mention: previous allergic reactions to GLP-1s or similar medications, kidney disease or history of kidney problems (relevant for dehydration risk), pancreatitis history (relevant if presenting with abdominal pain), gallstone history (relevant for biliary complications), thyroid disease or nodules (relevant to assessment of neck symptoms), nausea/vomiting severity and duration since injection, any missed recent injections or dose skipping. Symptoms to describe clearly: if abdominal pain, specify location (epigastric, right upper quadrant, diffuse), severity (1-10 scale), radiation pattern (to back, shoulder, etc.), character (sharp, dull, cramping, constant vs. intermittent), associated symptoms (fever, vomiting, constipation/diarrhea, icterus/jaundice). If you have medical alert bracelet noting GLP-1 use, show it to ER staff. If you have prior medical records from telehealth provider, bring those (or request ER obtains them). Provide precise medication list (other medications you take) because GLP-1s can interact with some diabetes medications (increased hypoglycemia risk with insulin/sulfonylureas). The more clearly you communicate, the faster ER can make correct diagnoses.
Yes, absolutely disclose if you've taken more than prescribed. This is relevant to ER assessment because overdose may cause severe side effects and guide treatment decisions. Scenarios: If you double-dosed accidentally (e.g., forgot whether you injected Monday so injected again Wednesday), ER needs to know because this raises GLP-1 levels substantially and increases risk of severe nausea, vomiting, dehydration. If you intentionally escalated dose faster than prescribed (aiming to lose weight quickly), ER needs context. If you took multiple consecutive injections without proper spacing, ER needs to understand cumulative exposure. Overdose effects: No true "overdose" toxicity with semaglutide (no deaths documented from overdose alone), but excess GLP-1 causes severe side effects: severe nausea/vomiting leading to dehydration, severe hypoglycemia if on concurrent diabetes medications (insulin, sulfonylureas), severe diarrhea/constipation causing electrolyte abnormalities. ER treatment approach differs based on disclosure: if known high GLP-1 level from overdose, ER focuses on supportive care (IV fluids, antiemetics, monitoring). If ER doesn't know about overdose, they may spend time investigating other causes of severe nausea/vomiting unnecessarily. Disclosure helps: Speeds diagnosis by narrowing differential. Directs appropriate treatment (knowing overdose helps focus on electrolyte repletion, hydration). Prevents unnecessary testing. Prevents accidentally repeating medication if you're admitted (ER may hold GLP-1 injections if overdose documented). Non-judgment note: ER physicians are trained to manage overdoses and medication errors without judgment. Their goal is your safety, not criticism. Disclose honestly; they need accurate information to help you.