The private pathologist hired by Anna Nicole Smith to perform a second autopsy on her son said that Daniel Smith most likely died of cardiac arrhythmia.
It is known that the Lexapro was prescribed to Daniel Smith but it is unknown where he got the other two.
Methadone, Wecht said, is "a legitimate prescription drug for pain relief" and that Smith had "no known history of morphine addiction," reported People magazine.
Smith died in the Bahamas while visiting his mother in the hospital Sept. 10, three days after she gave birth to baby girl.
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