A pancreas transplant is a major operation. As with all types of surgery, there's a risk of complications.

Some complications can happen soon after the operation, while others may develop months, or even years, later.

One of the most common complications of a pancreas transplant is rejection of the donor pancreas.

This happens in between 10 to 15 out of 100 people who have a pancreas transplant.

Rejection is where the immune system recognises the transplanted pancreas as foreign and attacks it.

It usually occurs in the days, weeks or months after the transplant, although it can sometimes happen years later.

Immunosuppressant medicine can reduce the risk of rejection.

Symptoms of rejection include:

• pain and swelling in your tummy
• a high temperature
• being sick
• chills and aches
• extreme tiredness
• puffy, swollen ankles
• shortness of breath

Contact a GP or your transplant team as soon as possible if you have these symptoms.

Rejection can usually be treated by increasing your dose of immunosuppressant medicine.

The immunosuppressant medicines you need to take to prevent rejection can have a number of significant side effects.

These can include:

• an increased risk of getting infections
• shaky hands
• difficulty sleeping
• high blood pressure
• hair loss or thinning
• mood swings
• weight gain
• an upset stomach
• a rash
• weakened bones (osteoporosis)
• an increased risk of certain types of cancer, particularly skin cancer

Speak to your transplant team if you have any troublesome side effects.

Do not stop taking your medicine without getting medical advice first.

Immunosuppressant medicine will weaken your immune system and make you more likely to get an infection.

While taking the medicine, it's a good idea to:

• report any possible symptoms of an infection to a GP or your transplant team immediately – things to look out for include a high temperature, aching muscles, diarrhoea or headaches
• ensure your vaccinations are up to date – speak to a GP or your transplant team for advice about any additional vaccines you might need as some are not safe if you're taking immunosuppressant medicines
• avoid close contact with anyone who has an infection – even if it's an infection to which you were previously immune, such as chickenpox

To help prevent infection, you may be given antibiotics, antifungal medicine or antiviral medicine to take for the first few weeks or months after your transplant.

Blood clots can sometimes form in the blood vessels that supply the new pancreas, which can stop it working properly.

The risk of this happening is highest in the days after the operation, so you'll be closely monitored in hospital to check for any signs of a blood clot.

You'll also be given blood-thinning medicine to reduce the chances of a clot forming.

If a blood clot does develop in the new pancreas, the pancreas transplant will often need to be removed completely.

Blood clots can also form in other blood vessels after surgery, such as those in your legs (deep vein thrombosis) or supplying your lungs (pulmonary embolism), but taking blood-thinning medicine should help prevent this.

Pancreatitis is swelling of the pancreas and is common in the first few days after surgery.

Symptoms of pancreatitis include:

• a dull pain in your tummy
• feeling sick
• vomiting

Pancreatitis should pass within a few days.

But sometimes tubes may need to be placed in your tummy to drain any excess fluid off the donor pancreas.

In a few cases, it may be necessary to remove the donor pancreas.