Symptoms & Flare-Ups
Crohn’s symptoms can look different for every person, and your symptoms might shift over time. Some start mild and slowly, others start more suddenly. Knowing what’s typical — and what deserves a call to your doctor — helps you feel more in control of your body.
Crohn’s disease symptoms can be non-specific and mild at first or start suddenly and strongly. Some people experience symptoms for over a year before diagnosis. Symptoms may vary depending on the location of the inflammation, and can differ from patient to patient. They alternate with periods of remission (no symptoms) — either period may last for months or years.
General Symptoms
🚽 Gut & bathroom
- Abdominal pain (often in the lower abdomen)
- Diarrhea or loose stools, sometimes bloody
- Nausea and vomiting
- Soreness, tears, or skin irritation around the anus (perianal area)
💪 Body & energy
- Weight loss due to malabsorption (inflammation reduces nutrient absorption)
- Slower growth than expected (which often catches up once Crohn’s is treated)
- Anemia (due to ongoing inflammation or blood loss)
👄 Mouth
- Mouth redness, swelling, or ulcers
Extraintestinal Symptoms
🦴 Joints & bones
- Arthritis
- Osteoporosis
🧴 Skin
- Erythema nodosum (tender red or purple bumps, usually on the shins)
- Pyoderma gangrenosum (skin ulcers, often on the legs)
👁️ Eyes
- Episcleritis (redness and irritation of the white part of the eye)
- Uveitis (inflammation inside the eye that can cause pain and blurry vision)
🌡️ Whole body
- Fever
- Fatigue
- Restless leg syndrome
🩺 Liver & kidneys
- Liver function issues (e.g., inflammation of the liver or bile ducts, primary sclerosing cholangitis)
- Kidney stones
Possible Complications and Health Issues
Some teens may run into complications, but most don’t. The most common ones are strictures (narrowed sections of bowel) and fistulas (small abnormal channels between parts of the bowel or to nearby tissues). Other complications are rare and depend on where Crohn’s is most active. Your medical team watches for these as part of regular care, which is why check-ups matter — they help catch and manage issues early.
If things feel really heavy or you’re in crisis, please reach out — you don’t have to wait until it’s ‘bad enough.’ Visit findahelpline.com to find a free, confidential helpline in your country.
Flare-Ups
Flare-up symptoms often include typical Crohn’s disease symptoms. However, flare-ups can also present in different symptoms, including extraintestinal symptoms like joint pain, rashes, and fever.
While many symptoms may indicate a flare-up, a single day of stomach pain or diarrhea doesn’t always mean a flare-up. Ongoing or new symptoms that last for several days should be evaluated by your doctor.
🔍 What can trigger a flare-up?
The exact cause of Crohn’s flare-ups is unknown, but several factors may trigger them. Common triggers include:
- Specific foods (which vary by person)
- Smoking
- Stress
- Other diseases
- Certain medications (e.g., antibiotics, NSAIDs)
- Regular gaps in taking medication
⏱️ How long do flare-ups last?
Flare-ups vary in length, but they’re usually not something you’ll be stuck in for months. Today’s medications give your medical team good options to bring a flare under control.
Tip: Keeping a food & symptom journal can help you and your team spot what triggers your flares.
When to Seek Help
🩺 Not yet diagnosed?
- Loose or runny stools going on for more than 2 weeks
- Stomach cramps or pain, often in the middle or lower belly
- Blood when you go to the toilet
- Feeling sick to your stomach or vomiting
- Unintentional weight loss, on-and-off fever, or lots of tiredness
- Mouth sores, redness or swelling in your mouth, or soreness around the anus (perianal area)
- Symptoms that feel unrelated — like joint pain, skin rashes, or eye pain or redness
📋 Already diagnosed?
- More loose or runny stools than usual, several days in a row
- Stomach pain that is new, worse than usual, or hanging around for a week or more
- Blood when you go to the toilet recently
- New or unusual symptoms — joint pain, swollen joints, blurry or sore eyes, skin rashes, or mouth sores
🚨 Seek care right away
- Severe pain with high fever
- Feeling very dizzy or dehydrated
- Trouble keeping fluids down (nausea/vomiting)
- Rectal bleeding or vomiting blood
- Fast heartbeat with belly pain and fever