Other close relatives of a person with epilepsy have a risk five times that of the general population. Between 1 and 10% of those with Down syndrome and 90% of those with Angelman syndrome have epilepsy. Phakomatoses
Phakomatoses, also known as neurocutaneous disorders, are a group of multisystemic diseases that most prominently affect the skin and central nervous system. They are caused by defective development of the embryonic ectodermal tissue that is most often due to a single genetic mutation. The brain, as well as other neural tissue and the skin, are all derived from the ectoderm and thus defective development may result in epilepsy as well as other manifestations such as autism and intellectual disability. Some types of phakomatoses such as tuberous sclerosis complex and Sturge-Weber syndrome have a higher prevalence of epilepsy relative to others such as neurofibromatosis type 1.Tuberous sclerosis complex is an autosomal dominant disorder that is caused by mutations in either the TSC1 or TSC2 gene and it affects approximately 1 in 6,000-10,000 live births. These mutations result in the upregulation of the mechanistic target of rapamycin (mTOR) pathway which leads to the growth of tumors in many organs including the brain, skin, heart, eyes and kidneys. In addition, abnormal mTOR activity is believed to alter neural excitability. The prevalence of epilepsy is estimated to be 80-90%. The majority of cases of epilepsy present within the first 3 years of life and are medically refractory. Relatively recent developments for the treatment of epilepsy in TSC patients include mTOR inhibitors, cannabidiol and vigabatrin.
Medical uses
Propranolol is used for treating various conditions, including:

Cardiovascular
Hypertension
Angina pectoris (with the exception of variant angina)
Myocardial infarction
Tachycardia (and other sympathetic nervous system symptoms, such as muscle tremor) associated with various conditions, including anxiety, panic, hyperthyroidism, and lithium therapy
Portal hypertension, to lower portal vein pressure
Prevention of esophageal variceal bleeding and ascites
Anxiety
Hypertrophic cardiomyopathyWhile once a first-line treatment for hypertension, the role for beta blockers was downgraded in June 2006 in the United Kingdom to fourth-line, as they do not perform as well as other drugs, particularly in the elderly, and evidence is increasing that the most frequently used beta blockers at usual doses carry an unacceptable risk of provoking type 2 diabetes.Propranolol is not recommended for the treatment of high blood pressure by the Eighth Joint National Committee (JNC 8) because a higher rate of the primary composite outcome of cardiovascular death, myocardial infarction, or stroke compared to an angiotensin receptor blocker was noted in one study. Psychiatric
Propranolol is occasionally used to treat performance anxiety, although evidence to support its use in any anxiety disorders is poor. Its benefits appear similar to benzodiazepines in panic disorder with potentially fewer side effects such as addiction. Some experimentation has been conducted in other psychiatric areas:
Post-traumatic stress disorder (PTSD) and specific phobias (see subsection below)
Aggressive behavior of patients with brain injuries
Treating the excessive drinking of fluids in psychogenic polydipsia

PTSD and phobias
Propranolol is being investigated as a potential treatment for PTSD. Propranolol works to inhibit the actions of norepinephrine, a neurotransmitter that enhances memory consolidation.