{"id":17172,"date":"2025-10-24T11:27:59","date_gmt":"2025-10-24T11:27:59","guid":{"rendered":"https:\/\/www.simpleonlinepharmacy.co.uk\/health-advice\/?p=17172"},"modified":"2025-10-24T11:28:37","modified_gmt":"2025-10-24T11:28:37","slug":"wegovy-vs-mounjaro-side-effects","status":"publish","type":"post","link":"https:\/\/www.simpleonlinepharmacy.co.uk\/health-advice\/weight-loss\/wegovy-vs-mounjaro-side-effects\/","title":{"rendered":"Wegovy vs Mounjaro Side Effects: Similarities & Differences"},"content":{"rendered":"\n

If you\u2019re thinking of using treatment to manage your weight, you\u2019ve probably come across Eli Lilly\u2019s Mounjaro (tirzepatide) and Novo Nordisk’s Wegovy (semaglutide). Both are weekly injectable treatments that have become increasingly popular for weight management.<\/p>\n\n\n\n

For most patients, side effects play a major role in making a final decision. No one likes feeling ill, especially if you have a busy day-to-day life. So you might be wondering \u201cwhich injection has the least side effects?\u201d<\/p>\n\n\n\n

The good news is that side effects on both treatments are usually mild and temporary. But what are the differences (and similarities) between side effects on Wegovy vs Mounjaro<\/a>? Here, we compare the two.<\/p>\n\n\n\n

How Wegovy and Mounjaro Work: Similarities and Differences<\/h2>\n\n\n\n

Both Wegovy<\/a> and Mounjaro are weekly injections, where you increase your dose gradually over time. How quickly this increases will depend on your progress and how well you tolerate the treatment.<\/p>\n\n\n\n

You inject them under the skin, in the lower abdomen, thighs, or back of the arms.<\/p>\n\n\n\n

They both work by mimicking hormones that regulate appetite and help with blood sugar control. However, they are not identical. Wegovy acts on glucagon-like peptide-1 (GLP-1) hormone receptors. Mounjaro targets both GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptors.<\/p>\n\n\n\n

This dual action, it is believed, allows Mounjaro<\/a> to provide greater average weight loss results. In clinical trials<\/a>, patients taking Mounjaro lost an average of 22.5% of their starting body weight after 68 weeks. Meanwhile, those on Wegovy lost around 17% after 72 weeks.<\/p>\n\n\n\n

Common Wegovy vs Mounjaro Side Effects<\/h2>\n\n\n\n

\u201cSide effects [of Wegovy]<\/a> are often similar to those experienced on Mounjaro, with things like nausea or stomach upset,\u201d says Chief Clinical Officer Abdal Alvi<\/strong>. \u201cBut if you tolerate Mounjaro well, you\u2019ll likely manage Wegovy well too.\u201d<\/p>\n\n\n\n

Both medications work by suppressing appetite, helping you feel fuller for longer. This appetite-suppressing effect helps you lose weight, when combined with a healthy, balanced diet and exercise.<\/p>\n\n\n\n

Because Wegovy and Mounjaro work similarly, their side effects are also quite similar. The most common side effects for both medications tend to be stomach related.<\/p>\n\n\n\n

This is because both medications change how your body processes food. The appetite-suppressing effects can change what you\u2019re eating, leading to reduced dietary fibre and water intake.<\/p>\n\n\n\n

Very Common Side Effects<\/strong><\/td><\/tr>
Mounjaro<\/strong><\/td>Wegovy<\/strong><\/td><\/tr>
Feeling Sick (Nausea)<\/td>Feeling Sick (Nausea)<\/td><\/tr>
Being Sick (Vomiting)<\/td>Being Sick (Vomiting)<\/td><\/tr>
Constipation<\/td>Constipation<\/td><\/tr>
Diarrhoea<\/td>Diarrhoea<\/td><\/tr>
Stomach Pain<\/td>Stomach Pain<\/td><\/tr>
<\/td>Feeling Weak or Tired<\/td><\/tr>
<\/td>Headache<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Which Has Worse Side Effects, Wegovy or Mounjaro?<\/h2>\n\n\n\n

The side effects of Mounjaro<\/a> and Wegovy are fairly similar. And there are no completely unique side effects that belong only to one treatment. The difference often comes down to how frequently or how severely patients experience them.<\/p>\n\n\n\n

While both Mounjaro and Wegovy tend to cause similar side effects, some of these side effects can be more pronounced with Mounjaro.<\/p>\n\n\n\n

The British National Formulary (BNF) notes that gallbladder-related problems, such as gallstones, are reported more frequently with Mounjaro than with Wegovy. Its stronger effects on weight loss can also make fatigue or stomach upset feel more intense.<\/p>\n\n\n\n

Both medications carry a rare risk of inflammation of the pancreas (pancreatitis). And both include warnings about certain thyroid tumours observed in animal studies<\/a>. Although studies have not confirmed it in humans.<\/p>\n\n\n\n

Your prescriber will closely monitor your symptoms and tailor the dosing regime to best suit your personal needs.<\/p>\n\n\n\n

Side Effects Differ From Person to Person<\/h2>\n\n\n\n

Not everyone experiences side effects in the same way. Some people may tolerate Wegovy better, while others respond better to Mounjaro.<\/p>\n\n\n\n

Your medical history, other health conditions, medicines, and even genetic factors can all influence how your body reacts. Choosing between the two treatments is therefore not just about which is more effective, but also about how well you tolerate it.<\/p>\n\n\n\n

Whichever option you choose to go with, your prescriber will adjust the dose and schedule to best suit your progress and response. Most patients feel side effects more when just starting treatment or moving up to a higher dose.<\/p>\n\n\n\n

If you\u2019re on one of these treatments and are considering switching, discuss this with your prescriber. In general, if you tolerated one treatment well, you are likely to tolerate the other in a similar way. If you need support, contact us on 0141 774 5023<\/a>.<\/p>\n\n\n\n

When to Seek Medical Help<\/h2>\n\n\n\n

Both Mounjaro and Wegovy are authorised medicines. They\u2019re safe and effective when prescribed by a licensed clinician and purchased from a licensed pharmacy.<\/p>\n\n\n\n

But there are rare serious side effects that require you to seek immediate medical attention, these include:<\/p>\n\n\n\n