Take a breath. You're going to be okay. The most important thing first: Semaglutide has a very wide therapeutic index (the margin between therapeutic dose and dangerous dose). The approved dose range goes up to 2.4mg/week for weight management. You've taken 2.5mg, which is only slightly above the max approved dose. People in clinical trials have received single doses of up to 4mg in PK studies without serious adverse events. Hypoglycemia risk: Very low in non-diabetic patients. Semaglutide's insulin secretion is glucose-dependent — it only stimulates insulin release when blood glucose is elevated. In the STEP trials, the rate of clinically significant hypoglycemia (<54 mg/dL) in non-diabetic patients was <1%, even at 2.4mg. Since you're not on sulfonylureas or exogenous insulin, your risk is minimal. What to expect: You will likely experience increased GI side effects over the next 2-5 days: - Nausea (possibly significant) - Reduced appetite (more than usual) - Possible vomiting - Possible diarrhea or constipation - Possible headache What to do: 1. Stay hydrated 2. Eat small, bland meals 3. Skip your NEXT scheduled dose (you've essentially pre-loaded) 4. Monitor for signs of severe dehydration if you vomit repeatedly 5. If you feel faint or have severe symptoms, then seek medical attention You do NOT need to go to the ER right now.

Oh thank god. I was literally shaking. So 2.5mg isn't dangerous? I just assumed double dose = dangerous like with most medications.

For most medications, yes, a double dose can be dangerous. But semaglutide is unusually forgiving because: 1. Flat PK curve: Even doubling the dose doesn't create a dramatic spike because semaglutide is heavily albumin-bound (~99%) and has slow absorption from the SC injection site. Your peak plasma level with 2.5mg will be maybe 40-50 ng/mL versus your usual ~25 ng/mL at 1.25mg. Not a dramatic difference. 2. No direct toxic mechanism at these levels: The drug works via receptor agonism — once GLP-1 receptors are saturated, extra drug doesn't cause additional downstream effects in a linear way. You hit a ceiling. 3. Self-limiting side effects: The main consequence is GI discomfort, which while unpleasant, is not medically dangerous. Compare this to, say, insulin: A double dose of insulin WOULD be an emergency because it directly lowers blood sugar regardless of your glucose level. Semaglutide doesn't work that way. As Dr.NateNeph said, skip next week's dose. Your steady-state will normalize within 2 weeks. Set a phone alarm or use a tracking app going forward to prevent repeats.

I did the exact same thing 3 months ago at 1.7mg (so took 3.4mg total). I was nauseated for about 3 days — worst on day 2. Couldn't eat much, felt like mild food poisoning. By day 4-5 I was back to normal. Skipped my next dose and resumed the following week at my normal 1.7mg. It's scary in the moment but you'll be fine. Just prepare for a rough couple of days GI-wise. Ginger tea and Zofran (if you have it) are your friends.