Wegovy Side Effects: What's Common, What to Watch For, and How to Track Them

The side effects most commonly reported on Wegovy reflect how semaglutide acts on GLP-1 receptors and slows stomach emptying — which is why digestion-related symptoms dominate the picture. According to NHS guidance on semaglutide, the most frequent are nausea, vomiting, diarrhoea, constipation, indigestion, burping, headache, fatigue and injection-site reactions. Many people find these are strongest in the first few days after starting or stepping up, and gentler thereafter.

Wegovy side effects in the first week

The first week of a new dose is usually when the body is adjusting most. People commonly report nausea or low appetite, a metallic taste, mild headache, and tiredness. Smaller, protein-first meals, steady hydration, and avoiding heavy, greasy or very sweet foods are coping strategies many people describe as helpful. If symptoms feel disproportionate or you can't keep fluids down, that's a reason to contact your prescriber or doctor rather than push through.

Wegovy 0.25 mg and 0.5 mg side effects (titration doses)

The lower starter doses exist precisely to ease the body in. Effects at 0.25 mg and 0.5 mg tend to be milder — some nausea, occasional looser stools or constipation, and fatigue — and often settle within a week or two. For more on the typical pattern, see how long GLP-1 side effects typically last, which applies broadly across these medicines.

Wegovy 1.7 mg and 2.4 mg side effects (maintenance doses)

At the higher 1.7 mg and 2.4 mg doses, GI effects can return briefly after each step-up before settling. Constipation is one of the most commonly reported persistent issues at higher doses — fibre, fluids and gentle movement help many people, and practical approaches to GLP-1 constipation overlap closely. Fatigue can also be more noticeable on maintenance doses, often linked to reduced calorie intake; why GLP-1 medicines can make you tired covers this in depth.

Wegovy side effects after 6 months

By around the six-month mark, many people find the prominent GI symptoms have settled and the day-to-day picture is steadier. Some report subtler effects — hair shedding (often related to rapid weight change rather than the medicine itself), dry or sensitive skin, and ongoing low appetite. Hair shedding on Wegovy and the related pattern on tirzepatide are common questions worth reading alongside.

Other commonly asked-about effects

• Anxiety and mood changes: some people report low mood, anxiety or changes in food-related thoughts. These deserve a conversation with your prescriber, especially if they're new or worsening.
• Blood pressure changes: some people see lower blood pressure as weight changes; if you take blood-pressure medication, your prescriber may want to review it.
• Skin: dryness, mild rash, or injection-site reactions (redness, itch) are reported. Rotating sites and a gentle moisturiser help many people.
• UTI symptoms or cough: these are reported less often and aren't a recognised direct effect of semaglutide, but worth flagging to a healthcare professional if persistent.
• 'Cancer' concerns: Wegovy carries a thyroid-related warning based on animal studies; this is one of the points your prescriber will have considered before prescribing. Any new lump, persistent hoarseness or trouble swallowing should be raised promptly.

Wegovy vs Mounjaro: are the side effects worse?

Both are prescription-only GLP-1 medicines and both produce a similar pattern of digestive side effects. Individual experiences vary widely — some people tolerate one better than the other, and that's a question for your prescriber, not for ranking online. A balanced look sits in GLP-1 weight-loss injection side effects compared and the broader Mounjaro side effects hub.

When to contact a healthcare professional promptly

Some symptoms always warrant prompt clinical contact rather than self-management: severe or persistent vomiting, signs of dehydration, severe abdominal pain (especially pain that radiates to the back — a potential sign of pancreatitis), upper-right abdominal pain or jaundice (possible gallbladder issues), signs of an allergic reaction, severe low blood sugar if you also take diabetes medicines, new lumps in the neck, persistent hoarseness or trouble swallowing, vision changes, or significant new mental-health symptoms. If anything feels severe, persistent or simply not right, contact your healthcare professional rather than wait.

Wegovy is also subject to additional monitoring (the ▼ symbol). Side effects can be reported through your national reporting scheme (such as the UK's Yellow Card scheme) — your prescriber can guide you on how to do this where you live.

The single most useful thing you can do with Wegovy side effects is notice your pattern — when they appear after a dose, what makes them worse or better, and whether they're truly improving over time. That's exactly what GLP Trackr is built for.

Log symptoms as they happen

The side-effect tracker lets you log nausea, fatigue, constipation, headache, mood shifts, skin or injection-site reactions and more, with a quick severity rating and optional notes. Over a few weeks the app surfaces patterns — for example, that your nausea peaks days one and two after your weekly shot and is gone by day four, or that constipation eases the week you hit your fibre and water targets. Seeing that on a chart is far more useful than trying to remember it.

Spot connections you'd otherwise miss

Because GLP Trackr also tracks your dose, injection site, food, water, sleep and mood, the insights and correlation views can show how those factors line up with how you feel. Many people find that a small change — earlier dinners, more protein at breakfast, better hydration on shot day — meaningfully changes their symptom picture. This is general lifestyle context to observe and log, not medical treatment; any decision about your dose or your medication sits with your prescriber.

Bring a clear summary to your prescriber

If you do need to talk to your prescriber or doctor about side effects, GLP Trackr's doctor report turns your logs into a clear summary — which symptoms, how often, at which doses, and how severe — so the conversation starts from real data instead of memory. That tends to make appointments much more productive.

Read more across the hub

For deeper dives on specific topics, the full GLP-1 side effects hub is the parent guide, and these related pages cover the most-asked questions: longer-term GLP-1 side effects, dealing with constipation, hair shedding on GLP-1 medicines, sulphur burps and reflux, and a general overview of commonly reported GLP-1 side effects. If you're also curious about the medicines themselves, what tirzepatide is and the 5 mg dose stage give useful neutral background.

A note on safety

GLP Trackr is a tracking and journaling app, not a substitute for clinical advice. If symptoms feel severe, persistent, or worrying — or you simply aren't sure — contact your healthcare professional. They know your full history and are the right person to decide what to do next.

Ready to make sense of your Wegovy journey? GLP Trackr captures every dose, every symptom and every win in one place, then turns it into insight you can actually use. Try it free for 7 days on the App Store or Google Play — no commitment, just clarity.