Botulinum toxin (BTX), a neurotoxin produced by the gram-positive, rod-shaped anaerobic bacterium Clostridium botulinum, was isolated in 1897 by Belgian scientist Professor Pierre Emile van Ermengem. BTX acts by blocking the release of acetylcholine at the neuromuscular junction. As a result of this chemodenervation, a temporary flaccid paralysis ensues. Different medical disciplines have taken advantage of this temporary paralysis to treat muscular hypercontraction. BTX was first approved by the US Food and Drug Administration in 1989 for use in patients with strabismus and blepharospasm. Since then, BTX has been used to treat a number of different neuromuscular disorders. Although not approved by the US Food and Drug Administration, BTX has been used successfully in urology to treat neurogenic and non-neurogenic detrusor overactivity, detrusor-sphincter dyssynergia, motor and sensory urge, and chronic pain syndromes.