Wegovy contains a GLP-1 medication known as ‘semaglutide’ and can be used as a type of treatment to support weight loss. As with all medications, there are some associated risks and potential side effects with taking Wegovy. These risks and severity or type of side effects will be different for every person, and it can be helpful to be aware of the most common side effects and what you may experience once you start this medication.
The most common side effects associated with Wegovy are headaches, fatigue and symptoms related to the digestive system. Other, less common, side effects include reactions at the injection site, hair loss and skin and facial changes. It is also important to consider the risks of nutritional deficiencies when taking weight loss medications.
Headaches and fatigue
Two of the most common side effects seen in people taking Wegovy are headaches and fatigue. Most people experience these at the start of taking the medication, or for a period of time after their dose has been increased. Making sure that you are staying hydrated and eating at regular intervals can help to reduce these symptoms, and they typically improve once the body has adjusted to the new dose of medication.
Side effects of the digestive system
The frequency of side effects depends a little on the dose that is being taken. These effects include:
- Nausea – affecting 40-45% of people
- Diarrhoea – affecting 25-30% of people
- Vomiting – affecting 20-25% of people
- Abdominal pain – affecting around 20% of people
- Constipation – affecting 20-25% of people and lasting a little longer than other digestive side effects
These issues are most commonly reported within the first few weeks of starting the medication or a dose increase, are generally mild-to-moderate in severity, and typically improve on their own as the body gets used to the medication or with appropriate dose adjustments. In studies, around 3-4% of people taking Wegovy decided to stop because of the digestive side effects.
Many of these side effects can be minimised or avoided by working with your clinical team to find the right dose for you and taking a proactive approach to hydration and nutrition, whilst occasionally using medication to offset side effects while your body adapts.
Injection site
As Wegovy is a medication delivered by injection, some people experience a minor degree of skin irritation, redness or itching at the injection site, which normally resolves on its own. This discomfort can be reduced by rotating injection sites between doses.
Hair loss
Hair loss is another reported side effect of Wegovy, affecting between 2% and 5% of people taking the medication in studies. Hair loss was mostly reported as mild and resolved on its own while continuing the medication. Of note, individuals with the most weight loss reported the most hair loss, suggesting that hair loss may also be related to the rapid weight loss, as seen in people not using GLP-1 medications, rather than just the medication itself.
Skin and facial changes
Significant weight loss with GLP-1 medications, such as Wegovy, can also result in a number of other effects, including changes to facial features (commonly referred to online as ‘Ozempic face’, although this can occur with any GLP-1 medication or rapid weight loss) or excess skin around the body. These changes occur because of the rapid and significant loss of fat underneath the skin, which reduces the skin's volume.
Nutrition
Significant changes to the amount and types of foods that individuals are eating when taking Wegovy, without additional guidance, can lead to deficiencies in essential elements of their diets, such as protein, vitamins and minerals. This can also contribute to problems with skin and hair. Taking Wegovy alongside dietary support helps to optimise nutrition and ensure that the body is getting all of the nourishment it needs.
Key messages
- The most common side effects of Wegovy affect the digestive system. Most of these are mild to moderate in severity and are associated with starting the medication or increasing the dose
- Wegovy can also commonly cause fatigue, headaches and skin irritation at the injection site
- Most side effects resolve on their own after a few weeks or with appropriate dose adjustment
- Significant and rapid weight loss can contribute to hair loss and changes to the appearance of the face and body due to excess skin
- Robust nutritional support whilst taking GLP-1 medications can reduce the risk of dietary deficiencies
What our clinical experts say
At Genwell, we focus on high-quality weight loss, helping you lose weight safely while maintaining strength, energy and metabolic health rather than focusing purely on rapid results. When weight loss is done properly, the benefits go far beyond the scales.
Dr Caroline Butler
Genwell reflections
Every treatment decision is about weighing up the risks and side effects vs the benefits of medication for each person. The majority of people find that side effects are manageable and tend to settle down once their body gets used to the new medication or new dosing.
The team at Genwell is here to support you on your journey: in many cases, side effects can be managed with the right advice and appropriate monitoring.