The invention relates to the use of a liquid or semi-solid formulation of botulinum toxin for the preparation of a medicament intended to treat a disorder characterised by bladder spasms (e.g. urinary incontinence due to unstable bladder or unstable detrusor sphincter, voiding complications due to detrusor overactivity or unstable detrusor sphincter, urinary retention secondary to spastic sphincter or hypertrophied bladder neck and neurogenic bladder dysfunction secondary to Parkinson's disease, spinal cord injury, stroke or multiple sclerosis or characterised by a spasm reflex), wherein said medicament is for administration by infusion into the bladder or by other methods that do not involve injection into the bladder wall.