Botox (Botulinum A toxin) is a powerful drug that acts to temporarily paralyze muscles when it is locally injected. Botox is known for its popular use in cosmetics, but it actually has far reaching medical applications. It is commonly used for diverse conditions like muscle spasticity, headaches, as well as the treatment of urinary incontinence.
Botox is a well-tolerated treatment and the application of this therapy ranges from simple conditions like overactive bladder to treatment of severely spastic bladders from neurological disease. Botox can be injected into the bladder as a short, outpatient procedure. The therapy last for 6-12 months and then is re-injected. There is no limitation to the duration of using this type of therapy.
How does Botox treat urinary incontinence?Botox has been used to treat urinary incontinence for many years. It acts to decrease the muscular contractions of the bladder. These bladder “spasms” can arise from routine overactive bladder, which commonly occurs in women with aging or they can be more serious in patients with neurogenic bladder from neurologic disease or injury. Bladder spasticity has a lot of different names; it is also called overactive bladder, detrusor overactivity, detrusor hyperreflexia, and neurogenic bladder.
How is Botox administered?Botox needs to be injected into the muscle of the bladder. First the bladder is flushed with local anesthesia, which is allowed to thoroughly numb the bladder. Then a scope is passed up the urethra (urine channel) into the bladder. A small needle is placed through the scope and several injections are made into the bladder designed to spread Botox throughout the muscle of the bladder. Most patients tolerate this procedure well.
How quickly does Botox work and how long does it last?Botox begins to work at about 1 week, but the full effect of the medicine may take up to 2 weeks. Botox is not permanent and will last about 6-8 months in the bladder. Botox has a prolonged effect in the bladder compared to other muscles where it may only last a few months.
What are the risks of Botox?
Botox acts to decrease the strength of the bladder’s natural contraction. It eliminates bladder spasm by this method. One potential side effect of this is urinary retention. In other words the Botox works to well and patients cannot void on their own, or they have some residual urine in their bladder that does not pass with normal urination. Some residual urine does not cause much problem, but if this residual urine is high, or a patient cannot void a catheter has to be placed or a patient has to periodically pass a catheter in order to drain their bladder. This complication is rare in patients with overactive bladder, because we limit the amount of Botox we inject.
In patients with neurogenic bladder from conditions like multiple sclerosis or spinal cord injury we use much more Botox than in a patient with overactive bladder. The reason for this is patients with neurogenic bladder often are dependent upon catheterization to start with. In these patients the goal is to inject enough Botox so the bladder does not contract at all. This will eliminate leakage from bladder spasms and patients often are dry in between catheterizations.
There have been very few instances of Botox ever causing systemic weakness. This is a risk of Botox therapy, but extremely uncommon.