Appendicitis or Just a Stomach Ache? How to Tell the Difference

Abdominal pain is one of the most common reasons people present to a hospital, and the overwhelming majority of episodes are benign. That is exactly why appendicitis gets missed — it starts looking like everything else.

What distinguishes it is not any single symptom but a pattern, and specifically how that pattern evolves over hours.

The classic sequence

Textbook appendicitis follows a recognisable order, and around two-thirds of patients follow it reasonably closely.

• It begins as a vague, poorly localised ache around the navel — hard to point to precisely
• Appetite disappears. This is often the earliest and most consistent feature, and patients frequently mention it only when asked
• Over four to twelve hours the pain migrates and settles in the right lower abdomen, becoming sharper and easy to point to with one finger
• Nausea and sometimes vomiting follow the pain — importantly, after it, not before
• A low-grade fever develops, usually under 38.5°C initially
• Movement makes it worse — coughing, walking, going over a speed breaker, or getting out of bed

How it differs from gastritis or acidity

Gastric pain is usually upper or central, comes and goes over days or weeks, is often related to meals, frequently improves after eating or with an antacid, and is associated with burning, belching and a sour taste. Appetite is usually preserved.

Appendicitis pain is progressive rather than intermittent. It does not improve with an antacid. It gets steadily worse over hours rather than fluctuating, and it kills the appetite completely.

How it differs from food poisoning or gastroenteritis

Gastroenteritis usually starts with vomiting or diarrhoea, and the abdominal pain is crampy, generalised, and eases somewhat after passing stool or vomiting. There is often a history of a suspicious meal, or others affected.

In appendicitis, the pain comes first and the vomiting later. The pain is focal rather than crampy and generalised, and it does not ease after passing stool. Diarrhoea is possible but is not the dominant feature.

How it differs from period pain and ovarian causes

In women, right lower abdominal pain has a longer list of possible causes — ovarian cyst rupture, ovarian torsion, pelvic inflammatory disease, ectopic pregnancy and mittelschmerz (ovulation pain).

Period pain is usually central and lower, cramping in character, recurs cyclically and is familiar to the patient. Ovulation pain occurs mid-cycle and is short-lived.

This overlap is one of the strong arguments for laparoscopic rather than open appendectomy in young women. If the appendix is found to be normal, the surgeon can inspect the ovaries and tubes through the same ports and identify the actual cause, which an open incision over the appendix does not allow.

The examination findings that matter

A doctor assessing you will look for a few specific signs. Understanding them helps explain why the examination is done the way it is.

• Tenderness at McBurney’s point — about two-thirds of the way from the navel to the right hip bone
• Rebound tenderness — pain that is worse when the examining hand is released than when it presses
• Guarding — involuntary tensing of the abdominal muscles over the area
• Rovsing’s sign — pressing on the left lower abdomen produces pain on the right
• Pain on hopping or on coughing, a simple and quite reliable test

Why you should not take a painkiller and wait

This is worth stating plainly, because it is extremely common. Taking a strong painkiller and going to sleep does two things: it masks the progression that would otherwise have prompted you to seek help, and it gives the appendix six or eight more hours to perforate.

The risk of perforation rises sharply after about twenty-four to thirty-six hours of symptoms. A perforated appendix turns a thirty-minute day-case operation into a longer procedure with a washout, a drain, three to five days in hospital, intravenous antibiotics and a real risk of a pelvic abscess afterwards.

If your pain settles completely and your appetite returns, it was probably not appendicitis. If it is still there and worse a few hours later, get assessed.

What happens at the hospital

Assessment involves examination, blood tests looking for a raised white cell count and CRP, a urine test, and in women of childbearing age a pregnancy test. Ultrasound is usually the first imaging, particularly in children, young women and pregnancy. A CT scan is the most accurate test and is used when the diagnosis remains uncertain or complications are suspected.

Scoring systems such as the Alvarado score combine these findings to estimate probability. No single test is perfect, which is why the overall picture matters more than any one result.

Special cases where it looks different

• Young children — often present with generalised pain, vomiting and refusal to eat rather than a clear right-sided story, and perforate faster
• Elderly patients — may have surprisingly little pain and no fever, and are frequently diagnosed late
• Pregnancy — the appendix moves upward as the uterus enlarges, so pain may be in the right upper abdomen
• Retrocaecal appendix — sits behind the caecum, producing back or flank pain and fewer classical signs
• Pelvic appendix — can cause urinary symptoms or diarrhoea, mimicking a urinary infection

The bottom line

Abdominal pain that has lasted more than six hours, is getting worse rather than better, has settled in the right lower abdomen, and has taken your appetite away should be assessed the same day.

It may well turn out to be nothing. The cost of a consultation and an ultrasound is trivial compared with the cost of a perforated appendix.