Botulinum Toxin (BTX-A)

botox_injectionBotulinum toxin (aka Botox) is neurotoxin produced by the bacterium Clostridium Botulinum. When found in contaminated meat, it can cause botulism, a potentially deadly disease in humans and animals. In 1928, researchers also discovered that it can block nerve transmissions. In the 1980’s, it was first used to treat some eye problems, including strabismus (crossed eyes) and uncontrollable blinking (belpharospasm). It has since been used to treat spasm of the lower esophageal sphincter, frown lines, TMJ, migraines, dystonia and patients with upper motor neuron syndrome, such as cerebral palsy. When injected into a tight muscle, botox can relax the contraction thus allowing for better movement and so forth.

In the bladder and/or pelvis, Botox has been studied with tight pelvic floor muscles (vaginismus), incontinence and IC/BPS. In the bladder, it is injected into the bladder wall in multiple sites during a hydrodistention procedure. Research studies have shown modest success. One study reported efficacy of 69% (1). Two studies reported high initial efficacy rates of 74% and 86% at three months.(2)(3) Another showed that frequency improved significantly at 3.5 months.(4) Effectiveness diminished over time, however, and at one year symptoms were indistinguishable from baseline values.(5) One study reported a low efficacy rate at 3 months with only 20% of patients exhibiting improvement.(6)

Botox was originally placed as a Step 5 option for treatment because of the mixed results but also the risk of profound side effects. Some patients may be unable to urinate voluntarily after the procedure and may need to self catheterize for several months before the effect wears off. However, the AUA updated their guidelines in September 2014 and reclassified Botox as a Step 4 treatment option because new research emerged which showed that 100u treatments are as effective as the 200u treatment yet was found to cause fewer adverse events. The AUA clearly states that Botox is not an appropriate treatment for those who are unable to self-catheterize. Other adverse events including dysuria, straining and bladder retention.

Botox has also been linked to far more serious side effects, including deaths. In 2008, the FDA announced Botox has “been linked in some cases to adverse reactions, including respiratory failure and death, following treatment of a variety of conditions using a wide range of doses”, due to its ability to spread to areas distant from the site of the injection. (7)

Updated: 10/21/14 – Jill H. Osborne – includes the new AUA Guideline revision reclassifying Botox from Step 5 to Step 4.


  1. Smith JL: Case of the month. Interstitial cystitis. JAAPA 2004; 17: 48.
  2. Liu HT and Kuo HC: Intravesical botulinum toxin A injections plus hydrodistension can reduce nerve growth factor production and control bladder pain in interstitial cystitis. Urology 2007; 70: 463.
  3. Giannantoni A, Costantini E, Di Stasi SM et al: Botulinum A toxin intravesical injections in the treatment of painful bladder syndrome: a pilot study. Eur Urol 2006; 49: 704.
  4. Ramsay AK, Small DR and Conn IG: Intravesical botulinum toxin type A in chronic interstitial cystitis: results of a pilot study. Surgeon 2007; 5: 331.
  5. Giannantoni A, Porena M, Costantini E et al: Botulinum A toxin intravesical injection in patients with painful bladder syndrome: 1-year followup. J Urol 2008; 179: 1031.
  6. Kuo HC: Preliminary results of suburothelial injection of botulinum a toxin in the treatment of chronic interstitial cystitis. Urol Int 2005; 75: 170.
  7. FDA Notifies Public of Adverse Reactions Linked to Botox Use. Retrieved on 2012-05-06.