You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Disease", "Chemical"].

Please return the output as a JSON object of the format: {"Chemical" : ["Naloxone", ...], "Disease" : ["Hypotensive", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Contribution of sodium valproate to the syndrome of inappropriate secretion of antidiuretic hormone. We report the case of a 62-year-old man who was administered sodium valproate (VPA) and who subsequently developed the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). He had been taking VPA for treatment of idiopathic generalized tonic-clonic convulsions since he was 56 years old. After substituting VPA with zonisamide, the serum sodium level returned to normal. We consider this episode of SIADH to be the result of a combination of factors including a weakness of the central nervous system and the long-term administration of VPA.
{"Chemical": ["zonisamide", "sodium valproate", "VPA", "sodium"], "Disease": ["SIADH", "weakness of the central nervous system", "syndrome of inappropriate secretion of antidiuretic hormone", "tonic-clonic convulsions"]}