Side Effect – Indigestion

Indigestion: What it is, Symptoms & Treatment

Indigestion is a common side effect of GLP-1 medications (such as Mounjaro and Wegovy) and is usually mild and manageable. This happens because these medicines slow down how quickly food moves through your digestive system. Most people find that symptoms improve as their body adjusts over time. Please do not stop your GLP-1 medication without speaking to your provider.

GLP-1 injections work by slowing stomach emptying, reducing appetite and influencing gut hormone signals. As a result, food remains in the stomach for longer, which may increase the likelihood of:

• Heartburn
• Acid reflux
• Bloating or nausea
• A feeling of heaviness or “food sitting in the chest”

Symptoms of indigestion can include:

• Burning pain in the chest or throat (heartburn)
• Acid taste in the mouth
• Regurgitation (food/acid coming back up)
• Belching or burping
• Upper abdominal discomfort
• Nausea after eating
• Bloating or wind
• Worsening of symptoms at night or when lying flat

The risk of developing these symptoms is generally highest during the initial weeks of treatment and following dose increases, with symptoms usually improving as your body adjusts to the medication.

If you experience indigestion, here are some tips to help:

• Dietary Recommendations:

• Eat smaller meals (half portions)
• Eat slowly and chew well
•  Stop eating as soon as you feel full
• Avoid eating late,  finish food 3-4 hours before bed
• Avoid drinking large amounts during meals (sip instead)

• Foods & drinks to avoid

Some foods trigger reflux more strongly with GLP-1 medication:

Reduce or avoid:

• Greasy, fried food
• Spicy meals
• Tomato-based sauces
• Citrus fruits/juices
• Chocolate
• Peppermint
• Coffee/energy drinks
• Fizzy drinks
• Alcohol
• Very large high fatty meals

 Helpful choices:

• Small portions of lean protein
• simple carbohydrates (rice, oats, toast)
• Low-fat foods
• Soups and soft foods if symptoms are worse
• Ginger tea/peppermint may help nausea (but peppermint can worsen reflux in some)

• Supplements and Medical Intervention:

First line (quick relief)

• Gaviscon/alginates – coats the stomach and prevents acid reflux. This is best taken after meals and before bed
• Antacids (Rennie) -neutralises acid for short-term relief

If symptoms occur most days:

• Proton Pump Inhibitors (PPIs) are available to buy over the counter (omeprazole, esomeprazole). These reduce acid production and can be very effective if reflux is frequent.

Other medication & indigestion remedies (antibiotics, levothyroxine, iron, bisphosphonates):

• Reflux medication may affect absorption
• GLP-1 medication slows stomach emptying, which can delay the effect of oral medicines

 Separate your doses where possible and ask a pharmacist if you are unsure about this.

If you are experiencing symptoms most days, and need reflux medication daily for more than 1–2 weeks, speak to your GP.

• Lifestyle adjustments:
• Sleep with your head raised – use extra pillows or raise head of bed slightly
• Do not lie down after eating – stay upright for at least 2–3 hours
• Wear loose clothing – tight waistbands increase reflux
• Reduce smoking (if applicable)
• Maintain hydration – dehydration can worsen nausea/acid symptoms

Follow the prescribed dosing schedule, as increasing doses too quickly may worsen side effects. If your symptoms become difficult to manage, a temporary pause in dose escalation or a reduction in dose may be appropriate. Please discuss any changes to your treatment with your provider before adjusting your medication.

For most patients, indigestion is a temporary side effect that improves as the body adapts to GLP-1 medication. Many people find that symptoms improve or resolve with appropriate dietary changes, identifying food triggers, and supportive self care measures.

GLP-1 related indigestion often develops after starting treatment or following a dose increase. It may follow a predictable pattern linked to these changes. Keeping a food diary can help identify contributing factors and support symptom management.

Indigestion does not affect the absorption or effectiveness of injected GLP-1 medications. However, if bloating persists, it may impact your appetite, hydration, and overall wellbeing. If your symptoms continue or worsen, please seek advice from your healthcare provider.

When to Seek Urgent Medical Advice

Please contact your GP or your local Out of Hours service as soon as possible if you experience:

• Frequent acid reflux or regurgitation that affects daily life
• Ongoing nausea, bloating, or upper abdominal discomfort
• Difficulty eating or drinking due to symptoms
• Indigestion that is worsening over time or not responding to self care measures
• New or unexplained indigestion alongside other ongoing health concerns

Call 999 or go to your nearest A&E immediately if you experience:

• Severe chest pain or pressure (especially if spreading to your arms, back, neck, or jaw)
• Unexplained weight loss
• Indigestion or heartburn that is persistent or not improving
• Sudden, severe upper abdominal pain that does not settle
• Vomiting blood or vomit that looks like coffee grounds
• Black, tarry stools or heavy rectal bleeding
• Difficulty breathing, collapse, or feeling faint alongside chest or abdominal pain
• Signs of a serious allergic reaction, such as swelling of the face, lips, tongue, or throat, or severe difficulty breathing

Important Safety Advice

It is important to use GLP-1 medications safely and in line with clinical guidance. Side effects can often be managed effectively when identified early and addressed appropriately.

Maintaining open communication with your provider is key to ensuring safe and effective treatment.

Remember:

• Do not ignore persistent or worsening symptoms
• Do not increase your dose without clinical advice
• If you have had a break in treatment, restarting at a lower dose may reduce side effects
• Ensure your GP is informed of any new or unusual symptoms

Additional support

If you are experiencing side effects or have any questions about your treatment, our clinical team is here to help.

If your symptoms are severe, worsening, or you feel they require urgent medical attention, please seek immediate advice from your GP, NHS 111, or attend your nearest A&E department if appropriate.

For all other queries:

• Book a free video consultation with one of our trained clinicians through our website. Appointments are available throughout the week, including daytime and evening sessions.
• Send us your question online using our form: https://forms.medicinemarketplace.com/251345635207050 A member of our clinical team will respond by email.
• Speak to us by phone by calling 0330 175 5747, and selecting option 3.

We are here to answer your questions and provide support throughout your treatment journey.

Written by: Uzma Dala MPharm (2238839)

Approved by: Shameela Adam MPharm (2070113)