Welcome to the PPRX Mounjaro Safety & Side Effects Guide.
This page gives you a clear, easy-to-read overview of the most important side effects you may experience while using tirzepatide (Mounjaro).
Most people only experience mild, short-term effects when starting treatment, but it is important to know what to expect and when to seek urgent medical help.
If you are ever unsure, our pharmacy team is here to support you.
This page is a summary only and does not replace medical advice.
Serious Mounjaro side effects – seek immediate medical help
Although uncommon, some side effects can be serious. Stop using this medicine and seek urgent medical attention if you experience:
Severe, persistent stomach or back pain that does not go away (possible acute pancreatitis). This may occur with or without nausea and vomiting.
Severe allergic reaction such as difficulty breathing, swelling of the lips, tongue or throat, difficulty swallowing, or a fast heartbeat.
Uncommon (may affect up to 1 in 100 people)
Inflamed pancreas (acute pancreatitis), causing severe stomach and back pain that does not improve. This is potentially life-threatening – seek medical help immediately.
Rare (may affect up to 1 in 1,000 people)
Severe allergic reactions including anaphylaxis or angioedema. Seek urgent medical help.
Very common Mounjaro side effects
(May affect more than 1 in 10 people. Usually improve as your body adjusts.)
Low blood sugar (hypoglycaemia) when tirzepatide is used in type 2 diabetes alongside sulphonylureas or insulin. Symptoms may include headache, drowsiness, dizziness, hunger, sweating, fast heartbeat or irritability.
Feeling sick (nausea)*
Diarrhoea*
Being sick (vomiting)*
Stomach (abdominal) pain
Constipation
*These effects are usually mild and tend to settle over time as your body gets used to the medicine.
Constipation, abdominal pain and vomiting are very common in weight-management treatment, but common in diabetes treatment.
Common Mounjaro Side Effects
(May affect up to 1 in 10 people.)
Low blood sugar when tirzepatide is used with metformin and a sodium-glucose co-transporter 2 inhibitor.
Allergic reactions such as rash, itching or eczema
Dizziness (more common in weight-management treatment)
Low blood pressure (weight-management treatment)
Reduced appetite (type 2 diabetes)
Indigestion or bloating
Burping or excess gas
Reflux/heartburn (GORD)
Hair loss (weight-management treatment)
Feeling tired
Injection site redness or itching
Fast pulse
Increased pancreatic enzymes (lipase and amylase)
Increased calcitonin levels
Gallstones
Uncommon Mounjaro Side Effects
(May affect up to 1 in 100 people.)
Low blood sugar when used with metformin
Weight loss in type 2 diabetes patients
Injection site pain
Gallbladder infection (cholecystitis) in weight-management treatment
Changed sense of taste
Altered skin sensation
Delayed stomach emptying
Reporting Side Effects
If you experience any side effects, speak to a doctor, pharmacist or nurse. This includes any effects not listed on this page.
You can also report side effects directly via the MHRA Yellow Card Scheme. Search “MHRA Yellow Card” in the Apple or Google Play Store or visit the MHRA website.
Reporting side effects helps improve the safety of this medicine for everyone.
Support From PPRX
If you are worried about any symptoms, have questions about your treatment, or need support during your weight-loss journey, our pharmacy team is always available to help.
Contact us at:
Phone: 020 8191 3034
Whats App: 07753411111
Email: Support@pprx.co.uk
Website: www.pprx.co.uk
