We have seen a strong family clustering for hyperhidrosis, suggesting a genetic component. In fact, at TSC, we have operated on many children brought to our clinic by parents who endured disabling symptoms themselves. The pathophysiology is not fully understood however a neural regulation malfunction is thought to be the culprit. A hyperactive sympathetic system that cannot be controlled by central thermoregulatory neurons in the hypothalamus appears to be the most likely etiology.