Wegovy Tablets Side Effects: Common, Serious and How to Manage Them

The most common side effects of Wegovy tablets are gastrointestinal, meaning they affect the stomach and digestive system.

These include:

• nausea
• vomiting
• diarrhoea
• constipation
• stomach pain
• bloating
• indigestion
• acid reflux
• burping
• reduced appetite
• fatigue
• headache
• dizziness

Most side effects are mild to moderate and tend to happen when the dose is being increased. They often settle once your body gets used to the medicine.

Source: Oral Semaglutide at a Dose of 25 mg in Adults with Overweight or Obesity

In the OASIS 4 trial, gastrointestinal side effects were reported in 74.0% of people taking oral semaglutide 25mg, compared with 42.2% of people taking placebo.

Wegovy tablets contain semaglutide, a GLP-1 receptor agonist. GLP-1 medicines help reduce appetite and make you feel fuller for longer.

They can also slow stomach emptying. This is one reason why people may feel sick, bloated, full quickly, or uncomfortable after eating larger meals.

Side effects are more likely if you:

• eat large meals
• eat quickly
• eat greasy, rich or spicy foods
• drink alcohol
• do not drink enough fluids
• increase the dose before your body has adjusted
• take the tablet incorrectly

If side effects are severe, persistent or worsening, speak to your prescriber. Do not increase your dose until you have received clinical advice.

Side effects can start within the first few days of taking Wegovy tablets, but they are most common when treatment begins or when the dose is increased.

Wegovy tablets are usually started at a low dose and increased gradually. This helps your body adjust and reduces the chance of severe side effects.

Further reading: Wegovy tablets dosage

For many people, side effects improve within a few days to a few weeks. Nausea, bloating and indigestion often settle once the body adapts to the dose.

Some side effects, such as constipation, may last longer and may need lifestyle changes or pharmacy advice.

If side effects do not improve, become severe, or stop you eating and drinking normally, you should contact your prescriber.

Wegovy tablets and injections contain the same active ingredient, semaglutide, so their side effects are broadly similar.

The main difference is how the medicine is taken.

Wegovy tablets are taken once daily on an empty stomach with a small amount of water. You must wait at least 30 minutes before eating, drinking anything else, or taking other medicines.

Wegovy injections are taken once weekly and do not have the same fasting rule.

Wegovy tablets are not necessarily gentler than injections.

Some people may prefer tablets because they avoid needles, but others may find injections easier because they are weekly and do not require a strict morning routine.

Further reading: Wegovy tablets vs injections

Very common side effects affect more than 1 in 10 people.

These may include:

• nausea
• vomiting
• diarrhoea
• constipation
• stomach pain
• headache
• tiredness
• indigestion
• acid reflux
• bloating

These side effects are usually not dangerous, but they can be uncomfortable. They should be monitored, especially if they affect your ability to eat or drink.

Common side effects affect up to 1 in 10 people.

These may include:

• dizziness
• burping
• wind
• reduced appetite
• gallstone-related symptoms
• low blood sugar, especially if used with insulin or sulphonylureas
• changes in taste
• hair shedding linked to rapid weight loss
• mild dehydration if vomiting or diarrhoea occurs

Speak to a healthcare professional if these symptoms become troublesome or do not improve.

Serious side effects are less common, but they need urgent medical attention.

Seek urgent help if you develop:

• severe, persistent stomach pain, especially if it spreads to your back
• repeated vomiting or diarrhoea
• signs of dehydration, such as very dark urine, dizziness or confusion
• swelling of the face, lips, tongue or throat
• difficulty breathing
• severe rash or itching
• yellowing of the skin or eyes
• sudden vision loss or rapidly worsening eyesight
• symptoms of low blood sugar if you also take diabetes medicines

Severe, persistent abdominal pain may be a sign of pancreatitis. Sudden vision changes may need urgent eye assessment.

Yes. Vomiting and diarrhoea can lead to dehydration, especially if symptoms continue for more than a short period.

Signs of dehydration include:

• feeling very thirsty
• passing little urine
• dark urine
• dizziness
• dry mouth
• weakness
• confusion

If you cannot keep fluids down, or you feel faint or very unwell, seek medical advice urgently.

Semaglutide has been linked in very rare cases to a serious eye condition called non-arteritic anterior ischaemic optic neuropathy, also known as NAION.

You should seek urgent medical attention if you notice:

• sudden loss of vision
• eyesight getting worse very quickly
• new severe visual disturbance
• vision changes in one or both eyes

If eye casualty is available in your area, attend urgently. Otherwise, attend A&E.

Pancreatitis is a rare but serious possible side effect of GLP-1 medicines.

Seek urgent medical attention if you develop severe, persistent abdominal pain, especially if the pain spreads to your back or is accompanied by nausea and vomiting.

If pancreatitis is confirmed, GLP-1 treatment should not usually be restarted unless advised by a specialist.