I’ve been on a GLP-1 for over two years. Injection day is muscle memory now: pen out of the fridge, shot, on with my morning.

That habit is what started nagging at me. When you hear “overdose”, you probably picture reckless misuse. What surprised me when I started looking into this wasn't just how often these mistakes are reported. It was how ordinary the circumstances were.

AD: The smartest way to hit your protein on a GLP-1

America’s Poison Centers reports GLP-1 calls up nearly 1,500% since 2019, with 22,966 exposure cases through 2025. Part of that is the growth in people using these drugs.

A study published in the Journal of Medical Toxicology in February 2026 examined 10,033 GLP-1 exposure reports to U.S. poison centers from 2012 through 2023.

Among cases reported after July 2021:

These are poison-center reports, not the share of users who overdose. The FDA has also documented compounded semaglutide cases where patients injected 5 to 20 times their intended dose, some requiring hospitalization.

I think people using compounded GLP-1 medications are at higher risk of dosing errors, simply because they often have to measure the medication themselves. There are three units for one question. Milligrams are the drug, milliliters are the liquid, and syringe units are just markings on the barrel. Only one of them tells you your dose.

Change the vial's concentration and the same "10 units" becomes a different dose. That's not a patient mistake, it's a confusing setup.

By the way, here are some great free GLP-1 calculators and tools to help you calculate and double-check your dose.

With prefilled pens, the risks can be different: selecting the wrong strength, using two pens by mistake, or forgetting that you've already injected.

In June 2025, someone on r/SemaglutideCompound shared what happened after their very first injection.

They were supposed to draw 8 units of compounded semaglutide into a syringe. Instead, they injected 80 units.

They realized the mistake almost immediately and contacted Poison Control.

Within a few hours, severe nausea started, followed by repeated vomiting. By the next morning, they were struggling to keep liquids down and ended up in the emergency room, where they received IV fluids and medication for nausea.

It took more than a week before they began feeling reasonably normal again.

Another Reddit user shared her experience on r/Zepbound in February 2025.

She had been combining a 10 mg pen and a 2.5 mg pen, with her doctor's approval, to reach a 12.5 mg dose.

One evening, exhausted from work and moving, she accidentally grabbed two 10 mg pens instead.

She didn't notice her mistake until a week later.

In the meantime, she had experienced severe diarrhea for about two and a half days, which she initially assumed was a stomach bug.

In March 2025, a tirzepatide user described accidentally doubling their dose after switching from one telehealth provider to another.

The new medication came with different dosing measurements. They misunderstood the conversion and only realized what had happened after injecting.

They later reported some nausea and fatigue.

What interested me even more were the replies. Other users described similar mistakes, including one who reported vomiting for seven days and visiting the emergency room twice for IV fluids.

These are real stories. Some people end up in the ER. Others get a few rough days. Most of what gets posted online is the worst case, because that's what people want to share when they're scared.

If it happens to you, don't panic. Call your doctor or Poison Control (US: 1-800-222-1222) and report it. Stay hydrated. Watch for the red flags: vomiting that won't stop, not keeping fluids down, fainting, confusion or severe abdominal pain. Those mean urgent care.

Stay safe.

Hey, I'm Eric. I built TrueCal after falling off the wagon with MyFitnessPal one too many times, and it's helped me lose 62 lbs this year. On a GLP-1 you're eating less, so what you do eat matters more, especially protein.

TrueCal makes tracking it easy. Snap a pic of your plate, say what you ate or scan a barcode, and the app figures it out for you, with the source behind every number, like the USDA food database.

If something looks off, just tell it what to fix. Works on iPhone, Android and the web.

Try TrueCal free