Efficacy of Amitriptyline for Painful Bladder Syndrome (PBS)

Study Summary

This is a randomized clinical trial study to test the efficacy and safety of amitriptyline in the treatment of patients newly diagnosed with painful bladder syndrome (PBS). PBS is defined by symptoms--frequent urination day and night and increasing pain as the bladder fills--according to the International Continence Society. The syndrome includes interstitial cystitis (IC), which has been estimated to affect as many as 700,000 people, mostly women. Estimates for PBS vary widely, but as many as 10 million people may suffer from this condition. Although amitriptyline is a Food and Drug Administration (FDA)-approved medication used for depression, the way it works makes it useful for treating the pain of fibromyalgia, multiple sclerosis, and other chronic pain syndromes. Prior small studies in interstitial cystitis (IC) suggested the drug may be a wise choice for this syndrome as well, because it blocks nerve signals that trigger pain and may also decrease muscle spasms in the bladder, helping to relieve the symptoms of pain and frequent urination.

Primary Outcome

The primary efficacy analysis was based on intent to treat, comparing the proportion of responders between treatment arms on a patient reported GRA recorded at 12 weeks or study withdrawal. The 7-point GRA queried, "As compared to when you started the current study, how would you rate your overall symptoms now?" The 7 response options were markedly worse, moderately worse, slightly worse, the same, slightly improved, moderately improved and markedly improved. Participants who indicated that they

Conditions Studied

Interventions

• OTHER Placebo
• DRUG Amitriptyline

Study Locations (10)