Wegovy pill side effects

Wegovy pills can cause a range of side effects, although studies show that most are mild and temporary. Stomach-related side effects are reported most often because semaglutide slows down the movement of food through your stomach, helping you stay fuller for longer and eat less.

Many people have no significant problems while using Wegovy, while others may notice side effects during the first few weeks of treatment or after increasing their dose.

Very common side effects

Very common Wegovy pill side effects may affect more than 1 in 10 people, and include:

• nausea
• vomiting
• diarrhoea
• constipation
• stomach pain
• headache
• indigestion
• tiredness (fatigue) or weakness

While very common side effects often settle on their own, make sure your doctor is aware, and speak to them if they get worse or are long-lasting.

Common side effects

Common Wegovy pill side effects can affect up to 1 in 10 people, and include:

• dizziness
• bloating
• burping
• excess wind
• acid reflux or heartburn
• gastritis (inflamed stomach)
• gallstones
• hair loss
• altered sense of taste
• unusual skin sensations, such as tingling or numbness
• low blood sugar in people with diabetes, which is more likely if you also take a sulfonylurea or insulin

Uncommon side effects

Uncommon side effects can affect up to 1 in 100 people taking Wegovy pills, and include:

• low blood pressure
• feeling faint when standing up
• faster heart rate
• delayed stomach emptying
• low blood sugar in people without diabetes
• raised pancreatic enzymes
• abnormal liver blood test results
• raised bilirubin levels, which may cause jaundice (yellowing of the skin or the whites of your eyes)

Serious side effects

Stop taking Wegovy pills and speak to a doctor, or call 999 in an emergency, if you experience any of the following serious side effects:

• changes in your vision (particularly if you have diabetes or diabetic eye disease already), contact a doctor straight away if you notice sudden vision loss, worsening eyesight, or significant changes to your vision
• pancreatitis (inflammation of the pancreas), symptoms include severe stomach pain that does not go away and may spread to your back, with or without feeling or being sick – this is a serious condition, speak to a doctor or go to A&E straight away
• kidney, gallbladder or bladder stones, speak to a doctor straight away if you get pain in your lower back, side, or abdomen, difficulty passing urine, or changes in the colour of your urine, skin or eyes
• a severe allergic reaction, symptoms may include swelling of the face, lips, tongue, or throat, difficulty breathing or swallowing, wheezing, dizziness, feeling faint, or a fast heartbeat – call 999 straight away if you develop these symptoms
• hip or pelvic fractures, although rare, Wegovy tablets may increase the risk of fractures in some people – go to A&E if you have a fall and develop severe pain around your hip or pelvis
• bowel obstruction, a severe form of constipation that may cause stomach pain, bloating, vomiting, and difficulty passing stools – this is a medical emergency and requires you to go to A&E straight away

If you're ever unsure whether a side effect is serious, contact your doctor, NHS 111, or seek emergency medical help depending on the severity of your symptoms. Make sure to also read the patient information leaflet before starting Wegovy pills.

Most side effects settle as you continue taking the Wegovy pill. However, serious side effects can develop at any time during treatment. Although they are treatable, they could cause long-term complications in some people.

Some side effects that may develop on the Wegovy pill include:

• pancreatitis – this is usually treatable but unfortunately there have been some cases where treatment hasn’t been successful. Acute pancreatitis may cause long-term problems if it becomes chronic
• gallbladder problems, including gallstones – these are usually treatable, but in rare cases, can cause complications
• kidney problems linked to dehydration – make sure you’re hydrated and speak to a doctor if you have severe vomiting or diarrhoea, especially if you cannot keep fluids down or already have kidney problems
• bowel obstructions- usually obstructions resolve without surgery but this can be needed in more severe cases
• blood sugar dips in people with diabetes taking other diabetic medications – your doctor may need to adjust your other medications to stop this from happening

Wegovy pill and cancer

In the US, Wegovy carries a boxed warning for thyroid cancer. This is based on early studies in rats that suggested semaglutide could potentially be linked to thyroid tumours. However, human research has found no significant cancer risk, and there have been no documented cases, but the possibility cannot be entirely ruled out.

It’s important to contact your doctor if you notice any potential symptoms, such as:

• a new lump or swelling in your neck
• difficulty swallowing or persistent throat issues
• a hoarse voice that does not go away
• unexplained shortness of breath

If you have any further questions or concerns about the risk of cancer while using Wegovy, please discuss them with your doctor.

“Any new symptoms that start after beginning Wegovy pills should be monitored. Wegovy pills are a new medication, and though they’ve been studied for several years, there’s still a chance they could cause a side effect not mentioned in the patient information leaflet or clinical trials.

It's worth discussing any side effects or symptoms with your doctor, so they can check whether it could be linked to the medication or something else. You can also report suspected side effects through the MHRA Yellow Card Scheme. If enough people report a side effect, this will be investigated.”

– Dr Crystal Wyllie, Online Doctor

For most people, side effects start within the first few days or weeks of treatment. It’s also common for them to happen after dose increases, as your body adjusts to higher levels of semaglutide. Once you get to the maintenance dose, side effects should settle.

Not everyone experiences side effects, and some people complete treatment without any noticeable symptoms.

How long do Wegovy pill side effects last?

Most side effects improve within a few days to several weeks as your body gets used to Wegovy. They may be likely to come and go as you make your way up the Wegovy pill dosage schedule, but once you’ve taken the maintenance dose for several weeks, side effects should have settled. If they have not, speak to your doctor.

In clinical trials, the most reported side effects were:

These side effects were reported to be mild and temporary, though constipation was reported to last longer than other side effects.

Do side effects get worse when I increase my dose?

Side effects can come back when you increase your dose, but there are no reports of them becoming more severe with a higher dose. However, some people may not be able to tolerate a higher dose and may need to stay on a lower dose for longer, or in some cases, permanently.

Here, we look at some of the most common Wegovy pill side effects and how to manage them when you get them.

Managing nausea and vomiting

To help manage nausea and vomiting:

• eat smaller meals more often and sip on plain water, making sure you’re staying hydrated
• choose plain foods like toast, crackers, rice, and pasta
• avoid foods that may make nausea worse, like rich, fatty, or spicy foods
• eat slowly and stop eating when comfortably full

Speak to a doctor if this is severe, is making it hard to eat or drink, or if you think you could be at risk of dehydration.

Managing diarrhoea

If diarrhoea develops:

• increase your fluid intake, sticking to plain water mostly
• avoid greasy, spicy, or rich foods that could make it worse
• limit caffeine and alcohol

Speak to a doctor if this is ongoing or severe, or if you think you could be dehydrated.

Managing constipation

Constipation may improve by:

• drinking more water
• increasing dietary fibre gradually, such as through fruit and vegetables, wholemeal or whole grain options, and pulses like beans or lentils
• staying physically active – even gentle exercise can help keep things moving

Speak to a pharmacist for advice on constipation, and a doctor if symptoms continue after trying over-the-counter remedies.

Managing headaches

To reduce headaches:

• stay hydrated with plenty of water throughout the day
• eat regularly, as eating too little can cause headaches
• prioritise sleep and rest until you feel better

You can use over-the-counter painkillers to help with headaches, but speak to your doctor if they do not work or if headaches persist.

Managing indigestion and heartburn

Indigestion and heartburn may improve if you:

• eat smaller portions, stopping when you feel full
• avoid lying down after food, which also means not eating too close to bedtime
• reduce spicy and fatty foods, and anything else that triggers your symptoms
• limit caffeine and alcohol, which are both known to cause/worsen heartburn

Wegovy tablets are not suitable for everyone. However, if you’re currently taking another GLP-1 medication, like Mounjaro or Wegovy, Wegovy pills are usually suitable to switch to.

Wegovy pills may not be suitable if you:

• have ever had an allergic reaction to semaglutide
• are pregnant
• are breastfeeding
• want to try for a baby soon, as semaglutide must be stopped at least 2 months before trying
• have severe gastrointestinal conditions
• have had certain serious side effects from GLP-1 treatment, such as pancreatitis
• have severe kidney or liver disease
• take certain diabetes medications

A doctor will check whether the Wegovy pill is suitable for you before prescribing it.

If Wegovy tablets are not suitable for you, there are several other prescription and over-the-counter weight loss treatments available. The best option will depend on your medical history, weight loss goals, and whether you prefer tablets or injections.

Alternative treatments include:

• prescription GLP-1 weight loss injections – like Mounjaro, Wegovy, or Nevolat, which are taken once weekly (except Nevolat, which is a daily injection), and work like Wegovy tablets to help reduce appetite and increase fullness
• prescription weight loss tablets – like Mysimba, which works by targeting areas of the brain involved in appetite and food cravings or orlistat or Xenical, which work by reducing the amount of dietary fat your body absorbs with meals containing fat
• over-the-counter weight loss tablets – like alli and Orlos, which are the same as orlistat but at half the dosage, and also work by reducing dietary fat absorption up to 3 times a day with meals that contain some fat

All weight loss medication must be taken alongside healthy lifestyle changes, including a calorie-controlled diet and regular exercise.

For the most part, the Wegovy pill and Wegovy injection side effects are very similar. There are some small differences, such as how often some side effects occur, and injections cause injection site reactions, which pills do not.

Very common side effects

Very common side effects happen slightly more often with oral semaglutide than with injections. Clinical trials reported gastrointestinal side effects in:

• 74% of people taking 25mg oral semaglutide
• 70.8% of people taking 7.2mg Wegovy injections

Nausea and vomiting were also reported slightly more often with Wegovy pills, which may be because it's absorbed through the stomach.

Injection site reactions

Injection site reactions only happen with Wegovy injections. This is a common side effect, and can include:

• redness
• itching
• swelling
• bruising

Switching injection sites can help, and injections can be taken in the upper arms (if you have someone to do it for you), the stomach, or upper thighs. You can also use numbing cream or an antihistamine if you get a reaction from the injection.

Can Wegovy pills cause blindness?

There is no evidence that Wegovy tablets directly cause blindness. However, semaglutide may worsen existing diabetic eye disease in some people with diabetes, which can lead to temporary vision changes. Very rarely, Wegovy can cause non-arteritic anterior ischaemic optic neuropathy (NAION), which may cause loss of vision in one of your eyes without any pain. This can be permanent. Speak to a doctor if you notice any changes in your eyesight.

Can semaglutide tablets cause hair loss?

Yes, though it's not semaglutide itself that is causing the hair loss, but the rapid weight loss that semaglutide can cause. Wegovy pills do not directly affect the hair follicles, but hair loss is still reported as a common side effect because losing weight quickly can cause the body to go into ‘stress’, causing temporary hair loss.

➤ For more information on why this happens and how to stop hair loss on Wegovy, see our Wegovy and hair loss guide.

Is the Wegovy pill safe?

Yes, the Wegovy pill is safe for most people. However, it’s not suitable for everyone, which is why a doctor must prescribe it to you and monitor your weight loss and any side effects. If side effects do not get better, Wegovy pills may be stopped by your doctor, especially if staying at a lower dose does not improve your symptoms.

Like all medications, the Wegovy pill has some serious side effects that it’s important to be aware of, so you know what to do if you get symptoms. Usually, the benefits of weight loss on your physical and mental health outweigh the risk of side effects, but if you’re worried, speak to your doctor.

Do Wegovy pill side effects worsen when drinking alcohol?

They might. Although alcohol does not directly interact with semaglutide, it can make symptoms such as nausea, dizziness, reflux, and dehydration worse. Limiting alcohol may help if you are experiencing side effects while taking Wegovy tablets.