How Crohn's disease affects the body

Inflammation can lead to abdominal pain, diarrhoea, urgency, nausea, or loss of appetite. When the intestine is inflamed, digestion and absorption may become less effective, which can contribute to tiredness or difficulty maintaining weight. Symptoms may ease and return over time, and their pattern differs between people.

Crohn's disease can also affect life outside the gut. Ongoing symptoms may disturb sleep, work, school, travel, or mood. Joint, skin, eye, or mouth symptoms can occur in some people and should be mentioned during review, even if bowel symptoms seem mild.

Keep a record of bowel changes, pain, appetite, weight changes, fatigue, and symptoms outside the gut. Eat regularly as tolerated and ask for dietetic support if food restriction, diarrhoea, or poor appetite is making nutrition difficult. Do not stop prescribed treatment because symptoms improve; maintenance care helps clinicians judge how the condition is behaving.

A GP Consultation can coordinate review and referrals. A Blood Test may help check for inflammation, anaemia, or nutritional concerns, alongside other assessments chosen for your symptoms.

Seek urgent help for severe or rapidly worsening abdominal pain, repeated vomiting, a swollen abdomen with inability to pass stool or gas, heavy rectal bleeding, fainting, or signs of dehydration. Contact your care team promptly for a sustained change in bowel habit, fever, worsening diarrhoea, or marked weakness.

Ask which symptoms suggest active inflammation, how nutrition and fatigue should be monitored, and whether symptoms outside the gut need another specialist. Ask what change in your usual pattern should prompt an earlier appointment.