Who prescribed the anti-seizure medicine? Tell that doctor what your son’s last sodium level was and when. Ask if there’s another drug you son could take that doesn’t have this side effect. Also, be sure to tell the nephrologist that the anti-seizure medicine has a side effect of hyponatremia and that using the stronger dextrose solution made your son feel like he was going to pass out. If there’s a blood pressure reading, the doctor will want to know that too. I suspect the nephrologist may not know about this side effect of that drug.