Does Mounjaro Cause Coughing? Side Effects Explained

Many patients prescribed Mounjaro (tirzepatide) for type 2 diabetes wonder whether does Mounjaro cause coughing as a side effect. Mounjaro is a dual GIP and GLP-1 receptor agonist administered as a once-weekly injection to improve blood glucose control. Whilst gastrointestinal symptoms such as nausea and diarrhoea are well-documented adverse effects, cough is not officially recognised as a direct side effect in UK regulatory documentation. This article examines the evidence surrounding Mounjaro and respiratory symptoms, reviews the medication's established side effect profile, and provides guidance on when to seek medical advice for any persistent cough.

What Is Mounjaro and How Does It Work?

Mounjaro (tirzepatide) is a prescription medicine licensed in the UK for the treatment of type 2 diabetes mellitus in adults. It belongs to a class of medications known as dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonists. Mounjaro is administered as a once-weekly subcutaneous injection and works through multiple complementary mechanisms to improve glycaemic control.

The medication enhances insulin secretion from pancreatic beta cells in a glucose-dependent manner, meaning it stimulates insulin release only when blood glucose levels are elevated. This reduces the risk of hypoglycaemia compared to some other diabetes treatments. Simultaneously, tirzepatide suppresses glucagon secretion from pancreatic alpha cells, which helps prevent the liver from releasing excess glucose into the bloodstream. These actions work together to lower blood glucose levels effectively.

Beyond its effects on glucose metabolism, Mounjaro also slows gastric emptying, which helps reduce post-meal blood sugar spikes and promotes feelings of fullness. Many patients experience weight loss whilst taking this medication, which can be beneficial for those with type 2 diabetes who are overweight or obese. Clinical trials such as SURPASS-2 have demonstrated the efficacy of tirzepatide in glycaemic control and weight management.

Mounjaro is typically initiated at a low dose of 2.5 mg weekly, which is for initiation only and not intended for glycaemic control. The dose is gradually increased over several weeks to minimise gastrointestinal side effects. The maintenance dose ranges from 5 mg to 15 mg weekly, depending on individual response and tolerability. Importantly, Mounjaro is not indicated for type 1 diabetes or diabetic ketoacidosis.

Patients should be aware that the delayed gastric emptying effect can reduce the absorption of oral medications, including oral contraceptives. Additional contraceptive measures are recommended for 4 weeks after starting Mounjaro and after each dose increase. As with all diabetes medications, Mounjaro should be used alongside appropriate diet and exercise modifications as part of a comprehensive treatment plan.

Common Side Effects of Mounjaro

Like all medicines, Mounjaro can cause side effects, although not everyone experiences them. The most frequently reported adverse effects are gastrointestinal in nature, particularly during the initial weeks of treatment or following dose increases. According to the Summary of Product Characteristics (SmPC), these include:

• Nausea – very common (may affect more than 1 in 10 people)

• Diarrhoea – very common

• Vomiting – very common

• Constipation – common (may affect up to 1 in 10 people)

• Abdominal pain or discomfort – common

• Decreased appetite – very common, contributing to weight loss effects

Other side effects that may occur include injection site reactions (redness, itching, or swelling), fatigue, and dyspepsia (indigestion). Hypoglycaemia (low blood sugar) can occur, particularly when Mounjaro is used in combination with insulin or sulphonylureas, though it is less common when used as monotherapy due to the glucose-dependent mechanism of action.

Regarding coughing specifically, there is no official link established between Mounjaro and cough as a direct side effect. Cough is not listed among the common, uncommon, or rare adverse reactions in the SmPC approved by the Medicines and Healthcare products Regulatory Agency (MHRA). However, upper respiratory tract infections, which may cause coughing, can occur in patients taking tirzepatide.

More serious but less common side effects include gallbladder problems (such as gallstones or inflammation of the gallbladder), which may present as right upper abdominal pain, fever, or jaundice. Severe gastrointestinal symptoms can lead to dehydration and potentially acute kidney injury. Pancreatitis (inflammation of the pancreas) is a rare but serious side effect that may present with severe abdominal pain radiating to the back.

Patients with pre-existing diabetic retinopathy should be monitored closely, as rapid improvements in blood glucose control may temporarily worsen retinopathy.

If you suspect you are experiencing side effects from Mounjaro, you can report them via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk or through the Yellow Card app.

When to Seek Medical Advice About Coughing

Whilst coughing is not recognised as a typical side effect of Mounjaro, any new or persistent cough warrants appropriate evaluation to identify the underlying cause. You should contact your GP or healthcare professional if you experience:

• A cough lasting more than three weeks

• Coughing up blood or blood-stained phlegm (haemoptysis)

• Severe breathlessness or difficulty breathing

• Chest pain accompanying the cough

• Unexplained weight loss alongside the cough

• Night sweats or fever

• Hoarseness lasting more than three weeks

These symptoms may indicate conditions requiring investigation, such as respiratory infections, chronic obstructive pulmonary disease (COPD), asthma, or, rarely, more serious pathology. It is particularly important for patients with diabetes to seek prompt medical attention for respiratory symptoms, as they may be at increased risk of certain infections.

If you have a persistent cough, it's worth reviewing other medications you may be taking. For example, ACE inhibitors (commonly prescribed for high blood pressure or heart conditions) are a well-known cause of persistent dry cough that may be mistakenly attributed to other medicines.

Seek immediate medical attention (call 999 or attend A&E) if you experience:

• Sudden, severe difficulty breathing

• Chest pain with breathlessness

• Coughing up large amounts of blood

• Signs of a severe allergic reaction (anaphylaxis), including swelling of the face, lips, tongue, or throat, severe rash, or difficulty breathing

Additionally, whilst taking Mounjaro, you should seek urgent medical advice if you develop severe abdominal pain that does not resolve, particularly if accompanied by nausea and vomiting, as this could indicate pancreatitis—a rare but serious side effect. Similarly, symptoms of thyroid tumours (such as a lump in the neck, hoarseness, or difficulty swallowing) should be reported promptly, although these are extremely rare.

If you are uncertain whether your symptoms require urgent attention, contact NHS 111 for guidance. Never discontinue Mounjaro without consulting your healthcare professional, as this could affect your diabetes control.

Managing Side Effects While Taking Mounjaro

Effective management of side effects can significantly improve treatment adherence and overall experience with Mounjaro. For gastrointestinal symptoms, which are the most common side effects, consider the following strategies:

• Eat smaller, more frequent meals rather than large portions

• Avoid high-fat, greasy, or spicy foods that may exacerbate nausea

• Stay well hydrated, particularly if experiencing vomiting or diarrhoea

• Take your time eating and chew food thoroughly

• Avoid lying down immediately after meals

• Consider eating bland foods such as toast, crackers, or rice if feeling nauseous

These symptoms typically improve over time as your body adjusts to the medication. The gradual dose escalation protocol is specifically designed to minimise gastrointestinal side effects.

If you experience persistent vomiting or diarrhoea, it's important to maintain adequate hydration to prevent dehydration and potential kidney problems. Seek medical advice if you notice reduced urine output, dizziness when standing, or if vomiting/diarrhoea continues for more than 24 hours.

For injection site reactions, rotate injection sites between the abdomen, thigh, and upper arm as recommended. Allow the injection pen to reach room temperature before administering, and ensure proper injection technique. If reactions persist or worsen, discuss this with your diabetes nurse or GP.

Monitoring for hypoglycaemia is important, especially if you take Mounjaro alongside other glucose-lowering medications. Recognise symptoms such as trembling, sweating, confusion, or palpitations. Your healthcare professional may need to adjust doses of other diabetes medications when starting Mounjaro.

If you have pre-existing diabetic retinopathy, be vigilant for any new or worsening visual symptoms and ensure you attend routine eye screening appointments, as rapid improvements in blood glucose can temporarily worsen retinopathy.

Women using oral contraceptives should use additional contraceptive methods for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase, as the delayed gastric emptying effect may reduce contraceptive efficacy.

Regular follow-up appointments are essential to monitor your response to treatment, assess side effects, and check your HbA1c levels. NICE guidance recommends ongoing review of diabetes medications to ensure optimal glycaemic control whilst minimising adverse effects.

If side effects become intolerable despite these measures, do not stop taking Mounjaro without medical advice. Your healthcare professional may adjust your dose, slow the titration schedule, or consider alternative treatment options. Maintaining open communication with your diabetes care team ensures that any concerns are addressed promptly and that your treatment plan remains appropriate for your individual circumstances.

Frequently Asked Questions