Botulinum
Botulinum toxin is the approved medical treatment in the United States and Canada. It weakens the muscles by blocking the nerve impulses transmitted from the nerve endings of the muscles.
The benefits begin 1-14 days after treatment and lasts for an average of three to four months. The success rate is up to 90% in stopping the spasms (twitching).
The side effects of this treatment may be drooping eyelids, blurred vision, double vision and excessive treatment. Side effects are usually short-term. Speak to your doctor for more details.
Drugs - no specific drug has been shown to be effective as of this time. Consult your neurologist for possible new medications.
Surgery - as a possible last resort.