Q What is interstitial cystitis?

Interstitial cystitis (also known as IC, or in English, Interstitial Cystitis) is characterized by symptoms such as:

  • A persistent sense of discomfort or pain in the lower abdomen, even though urine tests show no signs of infection
  • Pain that builds as the bladder fills with urine and eases after urination
  • Frequent urination with only small amounts passed each time

Interstitial cystitis is a condition in which chronic inflammation develops in the bladder wall, causing persistent pain alongside a frequent and urgent need to urinate. Over time, the bladder wall may become fibrotic (hardened) and shrink.

A defining feature of interstitial cystitis is the formation of abnormal new blood vessels in the bladder wall. Diagnosis is confirmed by identifying Hunner lesions — clusters of these abnormal new vessels — through cystoscopy. When no clear Hunner lesions are present but pinpoint bleeding (glomerulations) occurs upon bladder distension, the condition is referred to as Bladder Pain Syndrome.

Treatment options include dietary therapy, medication, hydrodistension, and intravesical instillation therapy. However, conventional treatments often fail to provide fully satisfactory results. More recently, a new endovascular treatment targeting the abnormal new blood vessels has been developed. For more details, please continue reading further down this page.

Q What are the symptoms of interstitial cystitis?

Bladder pain persists chronically. A characteristic feature is that pain develops as urine accumulates in the bladder and improves after urination. Because filling the bladder triggers pain, patients feel the urge to urinate frequently in order to avoid discomfort. Waking at night to urinate is also common.

Another hallmark of the condition is urgency — a strong, often overwhelming urge to urinate, with a feeling of being unable to hold on. Symptoms may also fluctuate in response to diet and environmental factors.

Anyone who suspects they may have this condition is encouraged to consider consulting a specialist.

Q What causes interstitial cystitis?

In interstitial cystitis, the proliferation of abnormal new blood vessels in the bladder wall is a defining finding on which the diagnosis is based. Under normal circumstances, blood vessels in the bladder wall are not prominent. In interstitial cystitis, however, abnormal vessel proliferation occurs, and these clusters of new vessels are referred to as Hunner lesions. In cases where no clear Hunner lesions are present but abnormal bleeding from the bladder wall is observed upon hydrodistension, the condition is classified as Bladder Pain Syndrome — and abnormal neovascularization in the bladder wall has been confirmed in these cases as well.

Why this abnormal neovascularization occurs remains unknown. Proposed mechanisms include inflammation of the bladder surface, neurogenic inflammation (a state of heightened nerve sensitivity), allergic responses, autoimmune disease, and microbial infection, though none has been definitively established.

More recently, a new endovascular catheter-based treatment targeting these abnormal vessels has been developed.

Q How is interstitial cystitis diagnosed?

Diagnosis is made by identifying Hunner lesions — areas of mucosal redness caused by clusters of abnormal capillaries — through cystoscopy. During this procedure, a measured volume of water is instilled into the bladder to distend it, and the presence of bleeding (glomerulations) is assessed as part of the diagnostic evaluation.

Q Is dietary therapy effective for interstitial cystitis?

Strict dietary management has been reported to be effective in controlling symptoms of interstitial cystitis.(※1) Implementing dietary changes is strongly encouraged.

Foods and drinks to avoid most strictly:

  • Alcohol
  • Artificial sweeteners (found in many soft drinks)
  • Preservatives, additives, and artificial flavorings (check ingredient labels)
  • Coffee and black tea (decaffeinated varieties are also not recommended)
  • Citrus fruits (oranges, mandarins, sudachi, kabosu, etc.)
  • Cranberry juice (beneficial for ordinary cystitis, but known to worsen interstitial cystitis)
  • Chili peppers and spices
  • Carbonated water

The following lists cover a wide range of foods and drinks, but individual responses vary considerably. It is important to test each item personally and assess its effect on your own symptoms. For beverages, symptoms typically appear within 2 to 3 hours of consumption. For foods, it takes 6 hours or more for digestion and renal excretion to occur.

1) Fruit

Generally well tolerated: apples, blueberries, watermelon, coconut
Often problematic: cranberries, citrus fruits, grapes, guava, kiwifruit, dried fruit with preservatives

2) Grains

Generally well tolerated: bread, rice, buckwheat noodles, pasta, wheat flour
Often problematic: bread with preservatives, sweetened cereals

3) Protein

Generally well tolerated: eggs, chicken, pork, beef, lamb, fish, shrimp, crab
Often problematic: smoked meats, sausages, smoked salmon

4) Seasonings and flavorings

Generally well tolerated: almonds, basil, coriander, garlic, rosemary
Often problematic: artificial seasonings, preservatives, fish sauce, soy sauce, miso, Worcestershire sauce, chili pepper, wasabi, ginger, mustard, curry powder

5) Beverages

Generally well tolerated: water, milk, almond milk, blueberry juice, chamomile tea, peppermint tea
Often problematic: alcohol, carbonated drinks, cranberry juice, orange juice, tomato juice, lemonade, soy milk, sports drinks, vitamin drinks, energy drinks

6) 4Sweets and snacks

Generally well tolerated: homemade cookies, homemade cake, vanilla ice cream, honey, fresh cream
Often problematic: commercially made cakes and cookies, potato chips, chocolate, cocoa, coffee-flavored ice cream, citrus sorbets

7) Vegetables

Generally well tolerated: asparagus, avocado, lentils, broccoli, cauliflower, corn, eggplant, cucumber, okra, spinach, mushrooms, zucchini, red bell pepper, potato, pumpkin, turnip, olives
Often problematic: onions, pickles, tomatoes, edamame
Keep a food diary. Gradually expand your personal list of foods that are safe for you, adding items one at a time.

Q Is cranberry effective for interstitial cystitis?

Cranberries and cranberry juice are generally known to be beneficial for ordinary bacterial cystitis. However, in interstitial cystitis, they frequently worsen symptoms. Consumption should be avoided.

Q What prescription and over-the-counter medications are available for interstitial cystitis?

Prescription medications available from medical institutions include Uralit (used to alkalinize the urine, as acidification increases bladder irritation), analgesics such as loxoprofen, diclofenac, and tramadol, and the anti-allergic agent IPD. Certain antidepressants and antihistamines may also be prescribed.

Over-the-counter options include herbal preparations derived from natural ingredients. Ryutan-Shakan-To and Jinsen-San are considered effective in alleviating symptoms of interstitial cystitis.

Q I am scheduled to undergo hydrodistension. What does the procedure involve?

Hydrodistension is performed under general or spinal anesthesia. A cystoscope — the same type of endoscope used in bladder and prostate surgery — is inserted through the urethra to examine the bladder. Water is then instilled into the bladder for approximately three minutes to distend and expand it. The procedure must be completed within a short timeframe, as prolonged distension risks damaging the bladder wall. A urinary catheter is left in place for one to two days after the procedure before being removed, after which the patient is discharged.

For a five-day hospital stay, the approximate out-of-pocket cost at 30% co-payment, including hospitalization fees, is around 80,000 yen.

Hydrodistension can be expected to provide pain relief, but the effect is typically temporary and symptoms usually recur. In general, the duration of benefit is approximately six months to one year.

Q I have had interstitial cystitis for four years. Why is it not getting better?

Most conventional treatments for interstitial cystitis are symptomatic rather than curative. While hydrodistension may appear to address the underlying problem, symptoms recur with high probability, and the procedure cannot be repeated indefinitely — repeated distension leads to fibrosis of the bladder wall and impairs its ability to store urine.

More recently, a new treatment approach has been developed that avoids these drawbacks: endovascular catheter-based therapy targeting the abnormal new blood vessels.

Q What surgical options are available for interstitial cystitis besides hydrodistension?

Surgical options beyond hydrodistension include fulguration (electrocautery of Hunner lesions) and total cystectomy (surgical removal of the bladder).

Fulguration is performed using a cystoscope, in the same manner as hydrodistension. It can produce dramatic short-term pain relief. Approximately 40% of patients have been reported to maintain symptom improvement at three years. However, repeated fulguration causes progressive fibrosis and loss of bladder elasticity, so the procedure cannot be performed frequently.

Total cystectomy is the most radical option and involves complete removal of the bladder. However, a phenomenon known as phantom pain — in which pain is felt in the area where the bladder once was — has been reported in some patients following surgery, meaning that pain may persist even after removal. Given the significant physical burden of this procedure, it should be considered with great care.

As described below, newer treatments targeting abnormal new blood vessels are also available and are worth considering.

Q My symptoms have not improved despite hydrodistension. Are there any new non-surgical treatments?

A completely new treatment approach known as endovascular therapy is now available, designed to reduce the abnormal new blood vessels responsible for the condition.

In interstitial cystitis, abnormal new blood vessels form in the bladder wall. Because blood vessels and nerves grow together, this neovascularization causes the bladder to become hypersensitive and gives rise to pain.

Endovascular catheter-based therapy — already applied to joint pain and other musculoskeletal conditions — has now been developed for the treatment of interstitial cystitis. Unlike a urinary catheter, this procedure uses an extremely fine catheter with a diameter of just 0.6 mm, which is introduced into the bloodstream and advanced to the area near the bladder to reduce the abnormal vessels. This treatment has attracted considerable attention as a promising option.

Q Can interstitial cystitis trigger other conditions?

It is not widely known that interstitial cystitis can directly cause other conditions. However, certain conditions are known to occur concurrently with greater frequency in patients with interstitial cystitis.

For example, there are reports indicating that patients with interstitial cystitis have a higher tendency to also develop irritable bowel syndrome and fibromyalgia.

For more details, consultation at a specialized medical institution is recommended.

Q My symptoms worsen with stress. What are effective ways to manage stress?

Effective approaches to reducing anxiety and stress include maintaining social connections, ensuring adequate intake of nutrients such as iron and protein, and practicing acceptance of pain and discomfort. Reviewing work demands and household responsibilities is also important.

In women, stress is frequently exacerbated by deficiencies in iron and protein. It is not uncommon for iron deficiency to be present even when standard blood tests do not indicate anemia. Protein deficiency also contributes to increased stress. Addressing these nutritional deficiencies can reduce stress levels and lead to improvement in symptoms for many patients.

It is also known that the more one wishes for pain or discomfort to disappear, the more prominent those sensations tend to become. Rather than trying to eliminate pain and discomfort, accepting their presence has been shown to reduce their intensity. This psychological approach is known as ACT (Acceptance and Commitment Therapy) and is offered at our clinic.

For those interested, consultation at a specialized medical institution is encouraged.

Q Are there any self-care measures to relieve the pain of interstitial cystitis?

Two approaches to relieving the pain of interstitial cystitis are introduced below.

1. Bladder training

Bladder training involves drinking slightly more fluid than usual to increase urine volume, then delaying urination briefly to allow the bladder to expand a little before going to the toilet. The aim is to keep the urine as dilute as possible to minimize bladder irritation, and to gradually increase bladder capacity by holding urine a little longer before voiding. However, if increasing fluid intake feels too uncomfortable, do not force it.

2. Morning walks

Morning walks are recommended because exposure to morning light promotes the release of serotonin in the brain. One of the functions of serotonin is to dampen pain signals. Aim for a walk of approximately 15 to 20 minutes during the early morning hours, on clear days when sunlight is available. Avoid walking for too long. Pleasantly absorbing morning sunlight enhances serotonin production.

References (※1) Oh-Oka H: Clinical Efficacy of 1-Year Intensive Systematic Dietary Manipulation as Complementary and Alternative Medicine Therapies on Female Patients With Interstitial Cystitis/Bladder Pain Syndrome. Urology 106: 50–54, 2017.

Author

Dr. Yuji Okuno
Dr. Yuji Okuno
I began my career as an interventional radiologist, which led to my research on pathological angiogenesis during graduate school. As first author, I published findings on related genes in Nature Medicine in 2012. Based on this work, I developed a novel embolization treatment for chronic musculoskeletal disorders, such as knee osteoarthritis and frozen shoulder, and was the first to report its safety and effectiveness. This approach is now being studied internationally.

-Career-
2006-2009 Fellow, Department of Radiology, Clinica ET, Yokohama, Japan
2009-2012 Researcher, Center for Integrated Medical Research, Keio University, Tokyo, Japan
2012-2015 Clinical Researcher, Department of interventional radiology, Edogawa Hospital, Tokyo, Japan
2015-2017 Director, Musculoskeletal Intervention Center, Edogawa Hospital, Tokyo, Japan
2017- Chief Director, Okuno Clinic., Tokyo, Japan