Final answer:
The symptoms of hyponatremia in infants include temperature instability, apnea, bradycardia, hypotension, difficulty feeding, irritability, limpness, seizures, bulging fontanel, stiff neck, and opisthotonos.
Step-by-step explanation:
The symptoms of hyponatremia in infants can include temperature instability, apnea (cessation of breathing), bradycardia (slow heart rate), hypotension (low blood pressure), difficulty feeding, irritability, limpness, seizures, bulging fontanel (soft spot), stiff neck, hemiparesis (weakness on one side of the body), and opisthotonos (rigid body with arched back and head thrown backward).