Arsenic is highly toxic and can enter the body through the gastrointestinal tract, skin or lungs. Acute arsenic poisoning can occur through ingestion of contaminated water, occupational exposure and deliberate poisoning.
Acute arsenic poisoning (AAP) can present with a number of features. Exposure to non-lethal amounts, less than 5 milligrams, leads to vomiting and diarrhea, which spontaneously resolve after a few hours . The lethal dose is exposure to more than 100 milligrams.
Poisoning can occur through accidental ingestion of contaminated water, alcohol, produce that has been treated with certain pesticides, and herbal medicines. Occupational exposure in industries that handle metals, paint, glass, and ceramics can also result in arsenic poisoning  . Arsenic can be ingested, inhaled or absorbed through the skin.
More severe gastrointestinal (GI) manifestations of AAP include abdominal pain, which is usually colicky, but may also appear as an acute abdomen, and passage of large volumes of watery diarrhea with blood. This may lead to severe dehydration, hypovolemia, and death. It is often described as bloody rice water as it is similar to cholera rice water stools. Hyper-salivation may be the only GI symptom in some cases . Systematic examination may show inflammation of the esophagus and stomach .
The cardiovascular effects of AAP are cardiomyopathy, arrhythmias and ECG changes. Pulmonary system effects may manifest as adult respiratory distress syndrome, pulmonary edema, or respiratory failure.
AAP can lead to several hematological ailments that are exemplified by bone marrow suppression leading to normocytic anemia or pancytopenia, disseminated intravascular coagulation (DIC), and leukocyte abnormalities. Hemoglobinuria, hematuria as well as the excretion of arsenic in urine, are both features of AAP. Other systemic signs of AAP are the presence of a garlic odor, caustic burns, dysphagia, gangrene, rash, acute renal failure, liver failure, and metabolic acidosis  .
Acute arsenic poisoning may be diagnosed if arsenic is detected in blood, hair or urine samples . Care should be taken to differentiate between organic and inorganic forms of arsenic, as the former is abundant in seafood, and is harmless. Severely ill patients may need close monitoring of their vital signs, as well as urine output.
Laboratory tests that may be requested are:
Imaging techniques that may be carried out are abdominal and chest X-rays, electrocardiography, and nerve conduction studies .