Interstitial Cystitis (Bladder Pain Syndrome)

What interstitial cystitis is

In IC, the bladder wall and its nerves become hypersensitive. Possible mechanisms include a defect in the protective inner lining of the bladder (the glycosaminoglycan layer), allowing irritants in urine to reach deeper tissue; inflammation and mast cell activity; and nerve "upregulation" so that normal bladder filling is felt as pain. In a minority, a cystoscopy shows Hunner lesions, distinct inflamed patches, which respond to specific treatments.

IC often occurs alongside other pain conditions, including irritable bowel syndrome, fibromyalgia, vulvodynia, migraine and chronic fatigue.

Symptoms

• pain, pressure or discomfort in the bladder or lower abdomen that gets worse as the bladder fills and better after emptying
• pain in the urethra, vagina, vulva, scrotum, penis or perineum
• frequent urination, sometimes 20 or more times a day in severe cases, often in small amounts
• urgency: a strong need to go, driven by pain rather than fear of leaking
• waking at night to urinate
• pain during or after sex
• flares lasting days to weeks, with calmer periods between

IC vs urinary tract infection and overactive bladder

Many people with IC are initially treated repeatedly for UTIs before the diagnosis is made.

Causes and risk factors

The cause is not fully known. Risk factors include female sex, a history of other chronic pain conditions, and possibly previous bladder infections or injury. Some medicines, notably ketamine and the bladder medicine pentosan polysulfate, are linked to bladder or eye problems, discussed with your doctor.

Diagnosis

IC is diagnosed when symptoms last more than 6 weeks and other causes have been excluded:

• urine tests and culture to rule out infection and blood
• bladder diary: recording fluid intake, urination frequency and volume
• pelvic examination to check for tender pelvic floor muscles, vulvar pain and other causes
• post-void residual measurement
• cystoscopy in selected people, especially with blood in the urine, to look for Hunner lesions or bladder cancer
• tests for endometriosis, stones or prostatitis where relevant

Treatment

Treatment is individualized and often combines several approaches.

Self-care

• Diet: many people find coffee, tea, soda, alcohol, citrus, tomatoes, artificial sweeteners and spicy foods trigger flares. An elimination diet helps identify personal triggers.
• Fluids: drink enough to keep urine dilute, but not excessive amounts.
• Bladder training: gradually lengthening the time between bathroom visits.
• Stress management: relaxation, CBT and mindfulness reduce flares.
• Heat or cold packs on the lower abdomen or perineum during flares.
• Loose clothing and avoiding long sitting periods.

Pelvic floor physical therapy

Many people with IC have tight, tender pelvic floor muscles. Manual therapy by a specialist pelvic physical therapist is recommended. Kegel strengthening exercises usually make IC worse and should be avoided unless advised.

Medicines

• Amitriptyline: reduces pain and urgency.
• Antihistamines such as hydroxyzine or cimetidine.
• Pentosan polysulfate: may help restore the bladder lining; requires regular eye exams due to a risk of retinal damage.
• Pain relievers: acetaminophen (paracetamol) or NSAIDs at the label dose; phenazopyridine short term for flares.

Bladder treatments

• Bladder instillations: medicines such as lidocaine, heparin or DMSO placed directly into the bladder through a catheter.
• Hunner lesion treatment: cautery, laser or steroid injection during cystoscopy, often very effective.
• Botulinum toxin injections into the bladder wall.
• Sacral neuromodulation for refractory frequency and urgency.
• Major surgery is rarely needed and reserved for severe, unresponsive cases.

Outlook

IC is usually long-term, with symptoms that come and go. Most people find a combination of treatments that significantly improves symptoms and quality of life. Treating coexisting pain conditions and mood also helps.

Frequently asked questions

What are the symptoms of interstitial cystitis?

The main symptoms are bladder or pelvic pain or pressure that worsens as the bladder fills and eases after urinating, frequent and urgent urination, waking at night to urinate, and pain during sex. Urine tests show no infection.

What foods trigger interstitial cystitis?

Common triggers include coffee, tea, carbonated drinks, alcohol, citrus fruits and juices, tomatoes, artificial sweeteners, chocolate and spicy foods. Triggers vary between people, so an elimination diet can help find yours.

Is interstitial cystitis the same as a UTI?

No. IC causes UTI-like symptoms, but urine cultures are negative and antibiotics do not help. It is a chronic pain condition of the bladder rather than an infection.

Can interstitial cystitis be cured?

There is no single cure, but symptoms can often be controlled well. Some people go into long remissions. Hunner lesion treatment can give significant relief for those who have them.