Living with Hereditary hyperekplexia
An inherited condition in which infants have stiff muscles and a strong startle reaction to sudden noise.
Understanding Hereditary hyperekplexia
The startle is set off by unexpected stimuli, especially loud noises. After a startle, babies become very rigid and unable to move for a short time. Some babies stop breathing during these episodes. Signs usually fade by age 1, but older people may still startle easily, have periods of stiffness that can cause falls, and tolerate crowds and loud noise less well. A few have seizures. It starts in the newborn period or infancy.
Signs & symptoms
Symptoms vary from person to person. GARD lists these among the most common:
- Strong startle reaction
- Stiff muscles (hypertonia)
- Muscle twitches when falling asleep
- Rigid periods after a startle
- Hernias
- Acid reflux
Not everyone has every symptom. GARD's list comes from the Human Phenotype Ontology.
Diagnosis
- 1Talk with your doctor
Share the symptoms you've noticed, when they started and your family health history. Notes and photos can help.
- 2See a specialist
Specialists who may be involved include brain and nervous system specialists, genetic specialists and seizure and epilepsy specialists.
- 3Ask which tests can help
Your care team will decide which exams and tests can confirm the diagnosis.
- 4Connect with expert centers
Epilepsy Foundation may keep lists of experts for this condition.
Care & treatment
- Care team
- Brain and nervous system specialists (neurologists); Genetic specialists (geneticists); Seizure and epilepsy specialists (epileptologist)
- Expert care
- Expert lists: Epilepsy Foundation
- Treatment
- GARD doesn't list specific treatments for this condition. Your care team will tailor care to your symptoms.
- Research
- Clinical trials and observational studies may be options. See the research section below.
General information, not medical advice. Your care team makes the decisions.
Everyday life
Living with a rare condition is easier with support.
- Connect with Epilepsy Foundation
- Keep notes on symptoms, changes and questions for appointments
- Ask about patient registries that help research
- Look into financial aid and travel resources for care visits
Quick facts
GARD says changes in genes (also called variants) cause this condition. It can be autosomal dominant or autosomal recessive.
Also known as: congenital stiff man syndrome; familial startle disease; hereditary hyperexplexia; kok disease; startle disease; stiff baby syndrome
Patient organizations
- Epilepsy FoundationEpilepsy · United States
Broader rare-disease groups
- Global GenesRare Diseases · United States
- National Organization for Rare DisordersRare Diseases · United States
- Genetic AllianceRare Diseases · United States
- RARE FoundationRare Diseases · United States
You are more than your diagnosis
Perspectives from people navigating life with Hereditary hyperekplexia.
Explore research for Hereditary hyperekplexia
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