Semaglutide Side Effects: What You Need to Know Before Taking It

When you hear about semaglutide, a GLP-1 receptor agonist used for weight loss and type 2 diabetes. Also known as Wegovy or Ozempic, it works by slowing digestion and helping your body feel full longer. It’s not magic—many people lose weight, but not everyone handles it the same way. The biggest problem? Nausea. Not just a little upset stomach—some people feel sick enough to skip meals or even stop taking it. That’s not rare. In clinical trials, over 40% of users had nausea, especially when starting or increasing the dose.

It’s not just nausea. Diarrhea, vomiting, constipation, and stomach pain show up often. Some people get dizziness or fatigue. These aren’t just side effects—they’re signals your body is adjusting. Most ease after a few weeks, but if they stick around, you need to talk to your doctor. There’s also a small but serious risk: pancreatitis, gallbladder problems, and kidney issues. People with a history of thyroid cancer or multiple endocrine neoplasia should avoid it entirely. The FDA added a black box warning for thyroid tumors in animal studies, even though it’s unclear if that applies to humans.

What’s often ignored? The mental side effects. Some users report mood swings, anxiety, or even thoughts of self-harm. It’s not common, but it’s real enough that doctors now screen for depression before prescribing. And if you’re taking other meds—like insulin or sulfonylureas—you could drop your blood sugar dangerously low. That’s not a side effect of semaglutide alone—it’s a combo risk. You can’t just grab it off the internet and hope for the best. This isn’t a supplement. It’s a powerful drug with real consequences.

People who do well on it usually start low and go slow. They drink water, eat smaller meals, and avoid greasy or sugary foods. Some take anti-nausea meds like ondansetron for the first few weeks. Others switch to a different GLP-1 drug if semaglutide doesn’t fit. The goal isn’t to push through discomfort—it’s to find a balance that works for your body. The posts below cover real experiences, comparisons with other weight-loss drugs, how to manage nausea, and what to watch for if things go wrong. You’ll find advice from people who’ve been there, not just textbook warnings. This isn’t about fear. It’s about knowing what you’re signing up for—and how to stay safe while you’re at it.