Botulinum toxin has been used by ophthalmologists since 1973 as a treatment for patients with crossed eyes (squints) and for severe facial spasm. BOTOX/DYSPORT inactive muscle contraction, in effect causing a regulated form of paralysis. It inhibits the release of acetylcholine at the joining site of the nerve to the muscle, so that the muscle never gets a chance to contract. By weakening the overactive eye muscles, BOTOX/DYSPORT provides an alternative to surgery. It is used extensively by ophthalmologists in the management of facial spasm (blepharospasm and hemifacial spasm). This spasm is often due to an unknown cause but can sometimes arise from irritation to the nerve supplying a facial muscle.

BOTOX/DYSPORT has also been found to improve neck banding which may be seen when one flares their neck. These bands can often be seen on the neck of older patients, even at rest. It is now (1998) been licensed for spasticity in cerebral palsy and is used for Oesophageal acalasia, a disorder of the gut.

The effects of BOTOX/DYSPORT injections usually last for a period of 4 to 7 months in most patients, however, repeat injections may give permanent results. Side effects are rare and usually relate to the amount of toxin injected and to the location of the injection eg too much near the upper eyelid muscle will cause droopy eyelid until it wears off. Care is taken to avoid this complication. Hypersensitivity reactions are very rare. There are no reported general side effects when doses for facial muscle spasm and wrinkle prevention are used.