Hello there....., In most patients with hemifacial spasm, the treatment of choice is injection of botulinum toxin under electromyographic (EMG) guidance. Chemodenervation safely and effectively treats most patients, especially those with sustained contractions. Relief of spasms occurs 3-5 days after injection and lasts approximately 6 months.... Compressive lesions need to be treated surgically. Microvascular decompression surgery may be effective for those patients who do not respond to botulinum toxin