Medically reviewed by Dr. Diala Alatassi, MD
Most semaglutide side effects are digestive and tend to appear when a dose is started or raised, but a few are serious enough to need prompt medical attention. Here is what San Antonio-area patients should know about common effects, practical ways to ease them, and when to call a provider.
Side effects are one of the main reasons people stop GLP-1 medications, and many are manageable with early planning and open communication with your prescriber. For adults in San Antonio, Alamo Heights, Schertz, Cibolo, Boerne, Helotes, and New Braunfels, knowing what to expect can make the first weeks less stressful.
Key Takeaways
The most common side effects of semaglutide are nausea, diarrhea, vomiting, and constipation, and they usually show up when treatment starts or the dose increases.
Serious risks are less common but include pancreatitis, gallbladder problems, dehydration affecting the kidneys, and a boxed warning about thyroid C-cell tumors.
Never change your dose on your own. Your prescriber adjusts it based on how you feel.
Tell every clinician, including dentists and anesthesia teams, that you take a GLP-1 medication before a procedure.
Common Digestive Side Effects
Semaglutide slows how quickly food leaves the stomach, which contributes to feeling full sooner but can also cause nausea, bloating, reflux, burping, diarrhea, or constipation. These effects are often strongest in the days after a dose is started or increased, and they often improve as your body adjusts. The STEP 1 trial found gastrointestinal effects were the most frequently reported, and they were mostly mild to moderate.
Practical Ways to Ease Them
These general tips may help, but ask your physician what is right for you. Eating smaller meals more slowly, stopping when you feel full, and limiting greasy, fried, or very sweet foods can reduce nausea. Sipping fluids through the day supports hydration and can help with constipation, as can fiber and regular movement. If symptoms are strong, your physician may adjust your dosing schedule or suggest other steps. Do not skip meals entirely or restrict protein, since maintaining muscle matters during weight loss.
Serious Side Effects: When to Get Help
Seek medical care right away for severe or persistent stomach pain that may radiate to the back, which can signal pancreatitis, and for pain in the upper right abdomen, fever, or yellowing of the skin or eyes, which can signal gallbladder problems. Vomiting or diarrhea that leads to dehydration can affect the kidneys, so call your provider if you cannot keep fluids down. Other warning signs include a lump or swelling in the neck, trouble swallowing, hoarseness, or shortness of breath, because semaglutide carries a boxed warning about thyroid C-cell tumors. Wegovy labeling also advises monitoring for depression or suicidal thoughts. In an emergency, call 911 or go to the nearest emergency room. The approved Wegovy labeling lists the full warnings.
Who Needs Extra Caution
Tell your physician if you have a history of pancreatitis, gallbladder disease, kidney disease, diabetic eye disease, or severe stomach problems, if you take insulin or sulfonylureas for diabetes because blood sugar can drop too low, or if you are pregnant or planning pregnancy. Semaglutide is not appropriate for people with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2. Because it slows stomach emptying, tell any team performing a procedure that requires sedation or anesthesia that you take it.
If Semaglutide Is Not the Right Fit
If side effects are hard to manage, a different option may suit you better. TeleSlim Clinic San Antonio also offers tirzepatide (Zepbound, Mounjaro), liraglutide (Saxenda), phentermine, phentermine-topiramate (Qsymia), naltrexone-bupropion (Contrave), orlistat, and metformin, along with setmelanotide for rare genetic causes of obesity after genetic confirmation. Compare them on the weight loss medications page. TeleSlim Clinic does not prescribe compounded medications.
Getting Care in San Antonio
Follow-up visits by secure video let your physician check side effects and adjust your plan. See how care is structured on the treatment page, read the FAQ page, or book a free consult. Read more about personalized weight loss planning.
Frequently Asked Questions
How long do semaglutide side effects last?
Digestive effects often ease within days to a few weeks after each dose change, but timing varies. Tell your provider if they persist or worsen.
Should I stop semaglutide if I feel nauseous?
Do not stop or change your dose without talking to your prescriber first. Mild nausea is common, and there are often ways to manage it.
Can semaglutide cause hair loss?
Some people report hair shedding during rapid weight loss, which is related to weight loss and nutrition changes rather than the drug alone. Ask your provider about protein and nutrient intake.
Can I drink alcohol on semaglutide?
Alcohol may worsen nausea and stomach upset and can affect blood sugar. Ask your physician what is appropriate for you.
Are side effects worse with higher doses?
Digestive effects can increase when the dose is raised, which is why doses are increased gradually under your prescriber's direction.
This article is for general education and is not medical advice. It was medically reviewed by Dr. Diala Alatassi, MD, double board-certified in Internal Medicine and Obesity Medicine. Talk with a licensed provider about whether any weight-loss medication is right for you.
