Forensic Medicine General 49acceb6 Most common symptom of thallium poisoning ? A Neuropathy B Abdominal pain C Headache D Visual disturbances High-Yield Explanation Ans. is 'B' i.e., Abdominal pain"Most common symptom of acute thallium poisoning is abdominal pain with nausea 6- vomiting and diarrhea or constipation".