<s>[INST] Hi, I have a close friend of mine (23 years old) who suffered from a sudden, unexpected death. He bloated in just a short period of time, and mouth foaming was observed (which is a big question on the probable cause). Half of his body (upper part) was in black-like appearance, and based on doctor's initial statement, this might be due to the blood vessel rupture. Few questions arise:What caused the occurence of mouth foaming?Is it normal to be bloated once dead?Is it cardiac-related factor as the person previously mentioned heart-ache?Some persons said it's a nightmare, how true is this attribute? [/INST] thanks for asking your questionfoaming from mouth is seen in epilepsy , seizure disorder.may be it was epilepsy followed by aspiration of gastric contents in the trachea which clogged the airway .this can be one of the reasons which caused cyanosis that is the bluish / black appearence , which is due to lack of oxygenated hemoglobin.this can be due to variety of diseases vessel rupture , pulmonary embolism , aneurysm , epilepsy , sudden cardiac arrest thanks may god bless you with good health </s>