Total 18 clinical symptoms reported for Hyperinsulinemic hypoglycemia, familial, 4  Very Frequent (8)Uncommon (4)Occasional (6)

Confusion	Lack of clarity and coherence of thought, perception, understanding, or action.   Synonyms:Confusion; Disorientation; Easily confused; Mental disorientation	Very frequent
Diarrhea	Abnormally increased frequency (usually defined as three or more) loose or watery bowel movements a day.   Synonyms:Diarrhea; Watery stool	Very frequent
Hypoglycemic encephalopathy	Brain damage related to a lowering of blood glucose below a critical level (around 30 mg/dl), which may lead to confusion, lethargy and delirium followed by seizures and coma. Prolonged hypoglycemia may lead to irreversible brain damage.	Very frequent
Intrauterine growth retardation	An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.   Synonyms:In utero growth retardation; Intrauterine growth failure; Intrauterine growth restriction; Intrauterine growth retardation, IUGR; Intrauterine retardation; IUGR; Prenatal growth deficiency; Prenatal growth failure; Prenatal growth retardation; Prenatal onset growth retardation; Prenatal-onset growth retardation; Small for gestational age infant	Very frequent
Lethargy	A state of fatigue, either physical or mental slowness and sluggishness, with difficulties in initiating or performing simple tasks. Distinguished from apathy which implies indifference and a lack of desire or interest in the task. A person with lethargy may have the desire, but not the energy to engage in personal or socially relevant tasks.   Synonyms:Dullness; Inaction; Inactivity; Languor; Lethargy; Slowness; Torpor	Very frequent
Neonatal hypotonia	Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period.   Synonyms:Hypotonia, in neonatal onset; Hypotonia, neonatal; Low muscle tone, in neonatal onset	Very frequent
Proportionate short stature	A kind of short stature in which different regions of the body are shortened to a comparable extent.   Synonyms:Proportionate small stature; Short stature, proportionate	Very frequent
Vomiting	Forceful ejection of the contents of the stomach through the mouth by means of a series of involuntary spasmic contractions.   Synonyms:Emesis; Throwing up; Vomiting	Very frequent