The appendix is a small, narrow pouch joined to the beginning of the large bowel, usually in the lower right side of the abdomen. Appendicitis means the appendix is swollen and infected. A blockage, sometimes from hard stool, can be involved, although the cause is not always known. As inflammation progresses, the appendix can burst and infection can spread inside the abdomen.

In an appendectomy the surgeon removes the appendix at its junction with the bowel and closes that point. The large and small intestines remain in place: food still passes through the digestive tract. People can live without an appendix. A removed appendix may be examined in a laboratory; ask your team how and when any result will be communicated.

The pouch opens into the caecum, the first part of the large bowel. A blockage can trap material inside, and infection and swelling can develop. The inflammation may remain localised or extend beyond the appendix; when it spreads to the abdominal lining, this is peritonitis. The pattern and pace vary, so the location or intensity of pain alone does not establish what is happening inside.

The operation closes the point at which the appendix joins the bowel, rather than removing the entire caecum or rerouting food. An unusually complicated finding may require a different procedure, which the team should explain afterwards. Laboratory examination may confirm the finding or identify a different or additional diagnosis.

Appendicitis needs urgent hospital assessment and treatment. Removing the inflamed appendix treats the source of the problem and reduces the risk of it bursting and causing a more widespread infection. If it has already burst, treatment may also address contamination or an abscess. The plan depends on the examination, tests and how unwell the person is.

Pain often starts around the belly button and moves to the lower right, but it can be less typical or occur elsewhere, including in pregnancy, young children and older people. Other conditions can cause similar pain. Clinicians may examine the abdomen, request blood and urine tests, imaging and, where relevant, a pregnancy test. There is no test that always establishes appendicitis, and sometimes observation in hospital helps clarify the diagnosis. In a strongly suggestive or potentially ruptured case, the team may recommend surgery without waiting for further tests.

Assessment considers the whole picture: when pain started, whether it is changing, examination findings, temperature, blood and urine results and, where appropriate, imaging. A normal-looking urine test does not by itself establish the cause of abdominal pain. Tests may be repeated or the examination reviewed because appendicitis can be difficult to distinguish from urinary, bowel or reproductive conditions.

In pregnancy, in children and in older people, symptoms may not follow the familiar pattern. If pregnancy is possible, telling the team helps them choose and interpret investigations. An emergency presentation takes priority over comparing elective recovery times: the question is what will treat the current infection safely, not simply which incision is smallest.

Surgery is the usual treatment. In selected cases where infection has not spread, antibiotics instead of immediate surgery may be considered, including when surgery carries high risk. Antibiotics do not remove the appendix and do not always resolve the problem permanently; further treatment, including surgery, may still be needed. The decision should take account of imaging, complications, health and the ability to return quickly if symptoms worsen.

In the US CODA trial, selected adults with imaging-confirmed appendicitis were assigned antibiotics or surgery. Some people treated with antibiotics subsequently had an appendectomy, and appendicoliths, hardened material in the appendix, were associated with a greater likelihood of subsequent surgery. The trial excluded some severe presentations, so it does not establish that antibiotics are suitable for every person with appendicitis or that delay is safe in a deteriorating patient.

Sometimes infection is contained in an appendix mass or abscess. The team may use antibiotics and, for an abscess, drainage, with the need and timing of any later surgery assessed individually. Observation by clinicians during diagnosis is different from deciding to wait at home without assessment. Ask what the plan is, how it will be reviewed and which changes require immediate reassessment.

The distinction between antibiotics instead of an operation and antibiotics alongside one is important. Antibiotics may be used as part of care for infection even when surgery is planned. If antibiotics are the initial treatment, ask how improvement will be assessed, what happens if it does not occur, and what access to reassessment is available after leaving hospital.

A contained mass is not the same as a free-spreading infection. If a collection of pus forms, the team may discuss draining it as well as antibiotics; later surgery depends on symptoms and findings. Ask how the collection will be followed and what the next decision point is, rather than assuming every abscess leads to the same operation.

Appendix removal is usually performed under general anaesthetic, so you are asleep. In keyhole surgery the surgeon makes small abdominal cuts, uses a camera and instruments to locate the appendix, separates it from the bowel and removes it. Gas creates space to see. The cuts are then closed. If the appendix has burst, the area may be cleaned; treatment depends on what is found.

Open surgery uses a larger incision, commonly in the lower right abdomen. It may be chosen from the start or become necessary during keyhole surgery, for example because of the findings or the need for safer access. A drain may sometimes be used when infection is present. A change to open surgery is a change of method, not proof that something has gone wrong. Ask your surgeon what they expect and what could alter the approach.

Before anaesthesia the team reviews your medicines, allergies, health and the last time you ate or drank. Urgency can affect how anaesthesia is planned. A cannula gives access for fluids and medicines, and breathing and circulation are monitored throughout. If the appendix has ruptured, the surgeon may wash the abdomen and sometimes leave a drain; the operation report should explain what was actually needed.

Afterwards, ask whether the appendix was inflamed or perforated, whether infection extended into the abdomen, and whether any unexpected findings changed the plan. Those details help explain why one person needs antibiotics, monitoring or a longer stay while another can go home sooner. If tissue was sent to the laboratory, agree who will check the result.

Removing the appendix treats the inflamed organ. As with any operation, bleeding or wound infection can occur. Infection can also collect inside the abdomen as an abscess. Adhesions, or internal scar tissue, can rarely cause a bowel blockage. The NHS also lists rare inflammation in a small remaining part of the appendix, called stump appendicitis. Injuries to nearby organs and anaesthetic complications are other risks to discuss.

A burst appendix can cause peritonitis, an abscess or sepsis and may make treatment and recovery more complex. The diagnosis is not always obvious before an operation, and the findings may change the plan. Your team can explain your personal risks and expected benefit more usefully than a single overall percentage.

Complications have different pathways. A wound infection affects the skin or deeper tissues around a cut; an abscess is a pocket of infection within the abdomen and may need further assessment, antibiotics or drainage. A burst appendix can cause infection of the abdominal lining and sepsis. These are reasons for the team to reassess worsening symptoms rather than assume all pain after surgery is routine healing.

Adhesions are bands of scar tissue inside the abdomen. They can sometimes obstruct the bowel later, while stump appendicitis describes inflammation in a small portion of appendix left behind. Both are uncommon, but new abdominal symptoms still deserve an assessment even after an appendectomy. The treatment team can consider surgery-related and unrelated explanations.

CODA compared an initial antibiotic strategy with appendectomy in adults with imaging-confirmed appendicitis at US centres. At 30 days, general health status met the trial’s prespecified non-inferiority criterion for antibiotics. By 90 days, some participants assigned antibiotics had undergone appendectomy; that outcome and complications were more frequent in the appendicolith subgroup. The primary health-status result is not the same as proving the treatments have identical complications or that antibiotics always avoid surgery.

CODA excluded people with septic shock, diffuse peritonitis, a walled-off abscess and other specified findings, although limited imaging evidence of perforation alone did not necessarily exclude someone. It studied adults, not children, and the initial report focused on early outcomes. A group average cannot establish whether an individual will respond, need later surgery or safely wait. The treating team must apply the evidence to the actual examination and urgency.

On the day of surgery the team watches breathing, blood pressure and alertness, offers pain relief and checks when you can drink and move. Some people need intravenous fluids or antibiotics, especially when infection has spread. Ask what was found, what medicines will continue and what milestones the team wants to see before discharge. Eating, drinking and bowel function are among the NHS checks. Stay can be longer after open surgery or a burst appendix, depending on recovery and the need for treatment.

During the first days at home, the practical tasks are checking and caring for dressings, taking the prescribed medicines, drinking and eating as tolerated, and getting up for gentle movement as advised. If antibiotics are prescribed, complete the course as directed. Constipation or diarrhoea may occur; ask the ward or a pharmacist for advice if bowel changes are troublesome, and seek help for worsening symptoms rather than adding restrictions on your own.

Abdominal and wound soreness and temporary constipation or diarrhoea can occur. The NHS says many people recover in one to two weeks, but recovery may take longer after complications. Follow your wound-care and medicine instructions and ask when to resume work, strenuous activity and driving. The ability to drive safely includes being able to make an emergency stop. Long-term digestion continues without the appendix, although persistent or new symptoms deserve assessment rather than an assumption about their cause.

As strength returns, ask about the demands of your particular work, lifting, sport and driving. You should be able to use the car safely and make an emergency stop; abdominal pain or sedating medication can matter. Complicated infection, open surgery or other health problems can alter the plan, so check in with the team if progress is slower than expected.

NHS England advises an urgent GP appointment or NHS 111 after an appendectomy for worsening wound soreness or redness, wound bleeding or pus, or a high temperature. For severe abdominal pain, confusion, blotchy or pale skin, or difficulty breathing, call 999 or go to A&E. Contact the surgical team about any other worsening or concerning symptoms and use your discharge instructions for local contact details. For urgent services outside England, see Urgent help above.