Yes, neurotoxins have many medical applications. When the discovery that BOTOX had cosmetic applications occurred, BOTOX was undergoing clinical trials for the treatment of strabismus and amblyopia. It largely treats disorders having to do with the muscles or nerves including:
Hyperhidrosis
Chronic migraines
Cervical dystonia
Urinary incontinence
Uncontrolled muscle spasms
Blepharospasm
Limb spasticity
Temporomandibular joint dysfunction (TMJ)