It can be very common to watch the news and hear about semaglutide — better known as Ozempic or Wegovy. Semaglutide was first developed to help manage type 2 diabetes under the brand name Ozempic. It’s now also approved under the name Wegovy for chronic weight management. Still, some people take Ozempic off-label for the same purpose.

If you’re about to start semaglutide for weight management, you might wonder what the first few doses will feel like and what changes to expect. Many MyObesityTeam members have turned to each other for answers about the drug. “Has anyone tried Ozempic? How is it going? Is it working for you?” one asked.

Another wrote, “I spoke with my primary care physician about getting the Ozempic shots today. She recommends them. Any thoughts, good or bad?”

If you feel like you’re drowning in a steady stream of information about Wegovy and Ozempic, you’re not alone. Here, we’ll discuss what you should expect when you start taking semaglutide.

How GLP-1 Drugs Work

Semaglutide is a glucagon-like peptide 1 receptor agonist, also called a GLP-1 medication. It works by mimicking the action of a naturally occurring hormone called GLP-1, which the body releases during meals to help regulate blood sugar levels.

By mimicking the GLP-1 hormone, semaglutide is able to regulate different processes related to digestion. When blood glucose (sugar) levels climb after eating, semaglutide raises insulin levels to bring down blood sugar.

Ozempic was approved by the U.S. Food and Drug Administration (FDA) in 2017 for the treatment of type 2 diabetes. In 2021, a higher-dose semaglutide treatment (Wegovy) was approved for chronic weight management. Wegovy is approved for adults with a body mass index (BMI) score in the obese range or those with a BMI in the overweight range who have at least one weight-related comorbidity.

In addition to helping the body adjust its glucose levels, GLP-1 drugs also help control appetite and digestion speed. They do this by slowing down the rate at which your stomach empties, which minimizes how much glucose is released into the bloodstream. Digesting food more slowly helps you feel full longer, which decreases your appetite.

Starting Semaglutide Injections

You’ll give yourself a semaglutide injection each week. Your doctor will likely tell you to rotate injection sites each week, choosing the left or right upper arm or thigh. The medication starts acting in the body the first time you have an injection, but you’ll likely have to continue using it for as long as two months before you experience the full effects.

During your first month of semaglutide, your healthcare provider will have you take a lower dose. This helps to reduce your risk of side effects as your body gets used to the drug. After your first four injections, your dose will likely be increased until you and your doctor find the steady dose you’ll maintain for the rest of your treatment.

Possible Side Effects of Semaglutide

Since semaglutide changes how your body digests food, the most common side effects of the drug are gastrointestinal (GI). For many people, these side effects will stop on their own within a few weeks as their body adjusts to the medication.

GI symptoms you may experience when starting a GLP-1 drug include:

• Nausea, with or without vomiting
• Diarrhea or constipation
• Bloated or uncomfortable abdomen
• More gas than normal
• Heartburn

One 2024 review of several studies found that people receiving semaglutide injections had a significantly increased risk of certain GI symptoms compared to those who didn’t use a GLP-1 drug. The study found that using the drug increased the risk of vomiting and nausea by more than four times and constipation and diarrhea by more than double. The risks of developing gallstones and other disorders of the gallbladder were also slightly increased. Adverse events and GI side effects, though not serious, prompted a significant number of people in the studies to stop taking semaglutide.

Less commonly, serious side effects can occur with semaglutide. See a healthcare professional as soon as possible if you experience side effects such as:

• Rash, hives, or other signs of an allergic reaction
• Blurred vision or other vision changes
• Intense abdominal pain, especially pain that extends to your back or that gets worse when touched or after you eat, which could be a symptom of pancreatitis (pancreas inflammation)
• Signs of dehydration, like headache or dark urine
• Lightheadedness or other signs of hypoglycemia (low blood sugar)
• Ankle, foot, or hand swelling or less urine than usual, which can be signs of kidney problems
• Pain or difficulty swallowing or a lump in the neck, which may be signs of thyroid cancer or benign thyroid tumors
• Inability to pass gas or stool, which can be signs of bowel obstruction
• Feeling full after barely eating and for a long time after, which can be signs of gastroparesis (when the stomach stops moving food into the digestive tract)

How To Manage Side Effects

Common side effects of semaglutide, like nausea and diarrhea, are usually temporary. Luckily, there are some steps you can take that may help resolve bothersome symptoms sooner.

Eat Smaller Meals

One thing that can help curb GI symptoms is eating smaller portions at a time. With your digestion moving slower than normal, it’s easy to overeat and feel sick. Reducing the amount of food that you eat at each meal and eating that food more slowly are a good place to start. These tips may be especially helpful to you if you’ve been vomiting.

Avoid High-Fat, Greasy, or Heavy Foods

Reducing the amount of fat you eat can also help with GI symptoms. Try to stick to low-fat foods, especially for two or three days after an injection. If you’re dealing with diarrhea, cutting out heavy dairy products can help your body as it recovers. Eating bland foods like crackers or foods with ginger or mint 30 minutes after your injection may help combat nausea.

Pay Attention to Your Fiber Intake

In general, it’s a good idea to reduce the amount of fiber you eat during the first few days after a semaglutide injection. If you’re experiencing diarrhea, you should continue on a low-fiber diet until your symptoms resolve. With constipation, you’ll want to do the opposite — focus on high-fiber foods that will help to get your bowels moving.

Drink Plenty of Water

Staying hydrated is an important part of being healthy. If you’re dealing with GI symptoms, it’s particularly important to drink enough water. Part of managing side effects like vomiting, diarrhea, and constipation is keeping yourself well hydrated.

Stick to Your Dosing Schedule

Since semaglutide changes how you digest food, side effects may occur as your body gets used to the new drug. Common GI side effects occur more often at the start of treatment and during dose changes. Usually these side effects are temporary and will resolve on their own within a few weeks. Following the dosing schedule outlined by your doctor will help your body get used to the medication.

Talk to Your Doctor

Don’t stop taking a GLP-1 without talking to your doctor first. If your GI symptoms or other side effects are bothersome, your healthcare provider can offer medical advice on how to deal with your symptoms. Keep in mind that, though rare, some side effects of semaglutide can be serious. Seek urgent medical care if you develop severe vomiting or diarrhea, intense stomach pain or tenderness, yellowing of the skin, or an inability to pass stool or gas.

Luckily, most semaglutide side effects tend to be short-lived and don’t require medical attention.

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Did you experience side effects after starting a GLP-1 medication? Let others know in the comments below.