| Reduced cerebral blood flow with orthostasis precedes hypocapnic hyperpnea, sympathetic activation, and postural tachycardia syndrome. |
| Common features include ataxia, hypotonia, episodic hyperpnea, newborn apnea, developmental delay, oculomotor apraxia, nystagmus, dysmorphic facies and polydactyly. |
| Severe overdosage may cause tachypnea or hyperpnea, hallucinations, hypertensive crisis, convulsions or delirium, but in some individuals there may be CNS depression with somnolence, stupor or respiratory depression. |
| Respiratory apnea followed the hyperpnea and lasted approximately 2 min when the animal was returned to the respirator. |
