The signs and symptoms are nonspecific, instantaneous and depend on the dose, route of entry and time lapse since exposure to poison. After inhalation exposure, patients commonly have airway irritation and breathlessness.[
4] Other features may include dizziness, easy fatigability, tightness in the chest, headache, nausea, vomiting, diarrhea, ataxia, numbness, paraesthesia, tremor, muscle weakness, diplopia and jaundice.[
7,
29,
35] In severe inhalation toxicity, the patient may develop acute respiratory distress syndrome (ARDS), cardiac failure, cardiac arrhythmias, convulsion and coma, and late manifestation of hepatotoxicity and nephrotoxicity may also occur.[
7,
25,
29,
36]
After ingestion, toxic features usually develop within few minutes. In mild poisoning nausea, repeated vomiting, diarrhea, headache, abdominal discomfort or pain and tachycardia are common clinical features, and these patients usually show recovery.[
7] On the other hand, in moderate to severe ingestional poisoning, the signs and symptoms of the gastrointestinal, cardiovascular, respiratory and nervous systems appear initially and, later on, features of hepatic and renal failure and disseminated intravascular coagulation may also occur.[
7,
37]
The toxicity of AlP particularly affects the cardiac and vascular tissues, which manifests as profound and refractory hypotension, congestive heart failure, electrocardiographic (ECG) abnormalities, myocarditis, subendocardial infarction or pericarditis. ECG abnormalities include rhythm disturbances, ST-T changes and conduction defects. Temporal correlation in ECG changes showed that during the initial 3–6 h, sinus tachycardia is predominant, in the 6–12 h period ST-T changes and conduction disturbances appear, while in the later period, arrhythmias occurred.[
38] In a study by Siwach
et al., the incidence of various arrhythmias on holter monitoring in patients of AlP poisoning showed ventricular tachycardia in 40%, ventricular fibrillation in 23.3%, supraventricular tachycardia in 46.7% and atrial flutter/fibrillation in 20% of the cases.[
39] The frequency of hypotension varies from 76% to 100%.[
40,
41] The exact mechanism of refractory shock is not clear; it may be due to several factors like myocardial damage, peripheral vasodilatation and fluid loss. In few cases of AlP poisoning, there was follow-up of cardiac function by echocardiography, revealing dysfunction of the left ventricle that was reversible over few days.[
42–
44]
Respiratory features may include cough, dyspnoea, cyanosis, pulmonary edema, respiratory failure and ARDS. Metabolic acidosis may be present probably due to the accumulation of lactic acid caused by blockage of oxidative phosphorylation and poor tissue perfusion. Patients may remain conscious till the late stage but can have manifestations like headache, dizziness, altered sensorium, convulsion and coma.[
7,
35]
Both hypo- and hypermagnesemia following AlP poisoning have been described in the literature, although their pathogenesis is not clear.[
40,
45,
46] Other uncommon findings in AlP poisoning are intravascular hemolysis, acute adrenocortical insufficiency, hepatitis, acute tubular necrosis, pancreatitis, hypo- or hyperglycemia, methhemoglobinemia, microangiopathic hemolytic anemia and disseminated intravascular coagulation.[
37,
47–
53] In follow-up among survivors, one-third of the patients had dysphagia due to esophageal complications, including esophageal stricture or tracheo-esophageal fistula.[
54]