Hemifacial Spasm


Hemifacial spasm (HS) causes muscles to contract on one side of the face. A person cannot control the spasm.


HS does not always have a cause. It may be due to:

  • A blood vessel pressing on the facial nerve
  • Facial nerve injury
  • Tumor

Muscles of the Face

Muscles of the Face
Copyright © Nucleus Medical Media, Inc.

Risk Factors

HS is more common in older women. It is also more common in people who are Asian.


Problems may be:

  • Twitching of the eyelid muscle that causes the eye to close
  • A mouth that is pulled to one side
  • Spasms of all the muscles on one side of the face


The doctor will ask about your symptoms and health history. A physical exam will be done. It will focus on the face.

Images of the head may be taken. This can be done with:

Nerve and muscle function may be tested. This can be done with electromyography (EMG).


The goal of treatment is to ease pressure on the nerve. This can be done with:

  • Injections of botulinum toxin to temporarily stop spasms
  • Antiseizure medicine

Some people may need surgery to reposition a blood vessel that is pressing on a nerve.


There are no known guidelines to prevent this problem.


National Institute of Neurological Disorders and Stroke
National Organization for Rare Disorders


Canadian Movement Disorder Group


Chaudhry N, Srivrastava A, et al. Hemifacial spasm: the past, present, and future. J Neurol Sci. 2015;356(1-2):27-31.
Hemifacial spasm information page. National Institute of Neurological Disorders and Stroke website. Available at: https://www.ninds.nih.gov/disorders/all-disorders/hemifacial-spasm-information-page. Accessed October 14, 2020.
OnabotulinumtoxinA. EBSCO DynaMed website. Available at: https://www.dynamed.com/drug-monograph/onabotulinumtoxina. Accessed October 14, 2020.
Last reviewed September 2020 by EBSCO Medical Review Board Teresa Briedwell, PT, DPT
Last Updated: 6/4/2021

EBSCO Information Services is fully accredited by URAC. URAC is an independent, nonprofit health care accrediting organization dedicated to promoting health care quality through accreditation, certification and commendation.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

To send comments or feedback to our Editorial Team regarding the content please email us at healthlibrarysupport@ebsco.com. Our Health Library Support team will respond to your email request within 2 business days.