Inflammatory bowel disease

Additional information

Inflammatory bowel disease

Inflammatory bowel disease, or IBD, is a long-term condition that causes inflammation in your digestive system. The two main types of IBD are Crohn’s disease (CD) and ulcerative colitis (UC). Both conditions cause swelling and irritation in your gut, leading to symptoms like tummy pain, diarrhoea, and fatigue. While they share some similarities, they also have important differences in how they affect your body and how they are treated [1] [2] [3].

Five key takeaways about inflammatory bowel disease (IBD)

1. IBD is a chronic condition that causes long-lasting inflammation in the digestive system, primarily affecting Crohn’s disease and ulcerative colitis, each with distinct symptoms and treatment approaches [1] [2].
2. The immune system plays a central role in IBD, mistakenly attacking the gut lining due to a mix of genetic, bacterial, environmental, and chemical factors, leading to inflammation and tissue damage [4].
3. Symptoms vary but often include tummy pain, diarrhoea, fatigue, and weight loss, with Crohn’s disease potentially affecting any part of the digestive tract and ulcerative colitis limited to the colon [1] [2].
4. Treatment focuses on reducing inflammation and maintaining remission through medications like aminosalicylates, corticosteroids, immunosuppressants, biologics, and promising new therapies such as Low Dose Naltrexone (LDN) [1] [12].
5. Living well with IBD means staying connected with your healthcare team, taking medications as prescribed, watching for flare-ups, maintaining a healthy lifestyle, and seeking support from specialist organisations [1].

If you’re living with IBD or suspect you might have it, understanding your condition and the treatment options available is key to managing your health and improving your quality of life. This guide will help you learn about the causes, symptoms, and treatments of IBD, with a special focus on new and promising therapies, such as Low Dose Naltrexone (LDN).

What causes inflammatory bowel disease?

IBD happens when your immune system, which normally protects you from infections, mistakenly attacks the lining of your gut. This causes ongoing inflammation, which can damage your digestive tract over time [4].

Several factors contribute to this immune system confusion:

• Genetics: Certain gene changes can increase your risk of developing IBD. For example, mutations in genes like CARD15 (also called NOD2) are linked to Crohn’s disease [4] [5] [6].
• Gut bacteria: Your gut is home to trillions of bacteria that usually help keep your digestive system healthy. When the balance of these bacteria is disrupted, it can trigger inflammation [4] [7].
• Environment: Lifestyle factors such as smoking and diet may increase your risk or worsen symptoms [4] [8].
• Immune system chemicals: Tiny messengers called cytokines help regulate inflammation. In IBD, these cytokines become imbalanced, leading to excessive inflammation [10].

What causes inflammatory bowel disease?

IBD happens when your immune system, which normally protects you from infections, mistakenly attacks the lining of your gut. Think of your immune system as a defence team that’s supposed to fight off harmful germs. But in IBD, this team gets confused and starts attacking your own gut cells, causing ongoing inflammation and damage [4].

How does this immune system confusion happen?

A careful balance of immune cells and friendly bacteria normally protects your gut lining. When this balance is disturbed, the immune system can overreact. Special immune cells called dendritic cells detect what’s going on and alert other immune cells, like T-cells, to respond. Sometimes, this response becomes too intense and persistent, leading to the symptoms of IBD [4].

The role of cytokines: the immune system’s messengers

Cytokines are tiny chemical messengers that immune cells use to communicate. In IBD, specific cytokines become overactive, leading to excessive gut inflammation. Key cytokines involved include:
• Tumour necrosis factor-alpha (TNF-?): Promotes inflammation and is a target for some IBD medicines [4].
• Interferon-gamma (IFN-?): Helps activate immune cells to fight infections but can worsen inflammation if uncontrolled [4].
• Transforming growth factor-beta (TGF-?): Plays a complex role, sometimes reducing inflammation but also involved in tissue scarring [4].
• Interleukins (IL-17, IL-22, IL-23, IL-9): These cytokines can both ramp up inflammation and help regulate it, showing how complex IBD is [4].

When these cytokines are out of balance, they cause the immune system to attack your gut lining, leading to the pain, diarrhoea, and other symptoms of IBD [4].

Crohn’s disease vs. ulcerative colitis: What’s the difference?

Crohn’s disease (CD)

Crohn’s disease can affect any part of your digestive tract—from your mouth to your anus. It causes inflammation that can extend deep into the layers of your gut wall, leading to complications such as narrowing (strictures), tunnels (fistulas), and ulcers [1].
Common symptoms include:
• Frequent diarrhoea (sometimes with blood)
• Abdominal pain and cramping
• Weight loss and poor nutrient absorption
• Fatigue
• Sometimes joint pain or skin problems
Crohn’s disease often runs in families, so if you have a close relative with the condition, your risk may be higher [1].

Ulcerative colitis (UC)

Ulcerative colitis affects only the innermost lining of your colon (large intestine) and rectum. Inflammation causes shallow sores (ulcers) and changes in the blood vessels of the colon [2].
Symptoms often include:
• Bloody diarrhoea
• Abdominal discomfort
• Urgency to pass stools
• Fatigue
Unlike Crohn’s, UC does not affect the full thickness of the gut wall and is limited to the colon [2].

Diagnosing IBD

Before starting treatment, it’s essential to rule out other conditions that can cause similar symptoms, such as:
• Irritable bowel syndrome (IBS)
• Gut blockages
• Coeliac disease
• Small intestinal bacterial overgrowth (SIBO)
Your doctor may use blood tests, stool samples, endoscopy, colonoscopy, and imaging scans to diagnose IBD and assess its severity [1], [2].

How is IBD treated?

The main goal of treatment is to reduce inflammation, relieve symptoms, and maintain remission (times when you feel well). Treatment plans are personalised based on your symptoms, the location and severity of your disease.

Common treatments for IBD

• Aminosalicylates (5-ASA): These are often used for mild to moderate ulcerative colitis to reduce inflammation. They are less effective for Crohn’s disease, especially in the small intestine [1], [2].
• Corticosteroids: Used to calm flare-ups quickly but not suitable for long-term use due to side effects [1], [2].
• Immunosuppressants (thiopurines): Drugs like azathioprine help maintain remission by suppressing the immune system. Regular blood tests are needed to monitor side effects [1], [2].
• Biologics: These are newer treatments that target specific parts of the immune system, such as anti-TNF drugs (e.g., infliximab). They can be very effective but may cause serious side effects in some people [1], [2].
• Combination therapy: Sometimes immunosuppressants and biologics are used together to improve outcomes and reduce flare-ups [11].
• Adjunct therapies: Antibiotics, probiotics, special diets, and nutritional support may also be recommended [1], [2].

Surgery

In cases where medicines don’t control symptoms or complications develop, surgery may be necessary to remove damaged parts of the bowel or treat fistulas and strictures [1], [2].

Low Dose Naltrexone (LDN): A promising new treatment

LDN is an exciting new therapy that works differently from traditional IBD medicines. Instead of suppressing the immune system broadly, LDN gently modulates it by temporarily blocking opioid receptors. This action encourages your body to produce its own natural anti-inflammatory substances called enkephalins and endorphins [12].

How does LDN help in IBD?

• Reduces inflammation in the gut lining
• Promotes healing of ulcers
• Improves symptoms and quality of life
• Has a good safety profile with fewer side effects than many immunosuppressive drugs [13], [14].

What does the research say about LDN for IBD?

Several studies have shown that LDN can help people with Crohn’s disease and ulcerative colitis, including those who haven’t responded well to other treatments:
• In one study, 89% of Crohn’s patients responded to LDN, and 67% achieved remission [15].
• LDN has been well tolerated in children with Crohn’s disease [16].
• Long-term use of LDN has been linked to reduced need for other medications like steroids and immunosuppressants [17].

Because LDN doesn’t suppress the immune system, it may be safer for long-term use and doesn’t increase the risk of infection like some other treatments.

Where can I buy LDN in the UK?

Getting your IBD medications, including LDN, through Courier Pharmacy is easy and discreet:

1. Complete an online consultation: Answer a few health questions securely on our website.
2. Pharmacist review: A registered pharmacist reviews your information and, if suitable, issues a prescription.
3. Fast, discreet delivery: Your medication arrives at your door in plain packaging.

Visit courierpharmacy.co.uk to start your consultation and take control of your IBD care today.

Living with IBD: Practical tips

• Stay in touch with your healthcare team: Regular check-ups help monitor your condition and adjust treatments as needed.
• Take your medicines as prescribed: Don’t stop or change doses without consulting your doctor.
• Watch for flare-ups: Symptoms like severe diarrhoea, blood in stools, fever, or sudden weight loss need urgent medical attention.
• Maintain a healthy lifestyle: Quit smoking, eat a balanced diet, and get regular exercise.
• Seek support: Organisations like Crohn’s & Colitis UK offer advice and community support.

If you have any questions or need personalised advice, our team at Courier Pharmacy is here to help. Start your online consultation today and take the first step towards better gut health.

Disclaimer: This article is for informational purposes only and does not replace professional medical advice.

References:

1. 1. NHS (2024) Crohn’s disease. Available at: https://www.nhs.uk/conditions/crohns-disease/ (Accessed: 16 October 2025)
2. 2. NHS (2024) Ulcerative colitis. Available at: https://www.nhs.uk/conditions/ulcerative-colitis/ (Accessed: 16 October 2025)

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1. J. Ploesser et al., “Low Dose Naltrexone: Side Effects and Efficacy in Gastrointestinal Disorders,” International Journal of Pharmaceutical Compounding 14, no. 2 (March/April 2010): 171–173.

15. P. Smith et al., “Low-Dose Naltrexone Therapy Improves Active Crohn’s Disease,” American Journal of Gastroenterology 102, no. 4 (April 2007): 820–828.

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