This is a tough condition to treat and even tougher to beat.  Women who suffer from it complain of chronic urethral pain or discomfort.  They report a constant sensation of "knowing that I have a urethra.".  It is maddening.  Therapy consist of identifying and treating any treatable conditions, like UTIs and the rare urethral diverticulum. In most cases, though, the cause remains a mystery and treatment involves a "shotgun" approach: try one thing then another etc until something works.  It is truly a frustrating malady.  
These therapies can work in some:
Tricyclics medications
Alpha blocker therapy
Androgen therapy
Corticosteroids
Topical anesthetics
Urethral dilations
How about Botox?   I'll let you know. 
Dr S
Hpv vaccine trial for treatment of topical wart
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Using vaccine for hpv to prevent genital wart recurrence clinical trial
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