Affected by dose, route, formulation and exposure pattern
Inhaled toxins more rapid than ingested
Inhalation exposure may cause syncope and death after only a few breaths
Early signs
CNS stimulation (Headache, anxiety, confusion)
Tachycardia, palpitations and hypotension
Tachypnea
Cherry-red color (rarely seen)
Late signs
Nausea, vomiting
Bradycardia, hypotension, arrhythmias, asystole
Coma, seizures (rare), Mydriasis
Bradypnea and pulmonary edema (non-cardiogenic), apnea
Renal failure
Hepatic Necrosis
Cyanosis
Rhabdo, bright red venules seen on fundoscopy
Inhaled toxins more rapid than ingested
Inhalation exposure may cause syncope and death after only a few breaths
Inhalation exposure may cause syncope and death after only a few breaths
CNS stimulation (Headache, anxiety, confusion)
Tachycardia, palpitations and hypotension
Tachypnea
Cherry-red color (rarely seen)
Nausea, vomiting
Bradycardia, hypotension, arrhythmias, asystole
Coma, seizures (rare), Mydriasis
Bradypnea and pulmonary edema (non-cardiogenic), apnea
Renal failure
Hepatic Necrosis
Cyanosis
Rhabdo, bright red venules seen on fundoscopy
Retrobulbar Optic Atropy (proposed)
Heavy smokers
Ataxic peripheral neuropathy
Konzo
Spastic upper motor neuron paraparesis seen in chronic ingestion of inadequately cooked casava
Heavy smokers
Spastic upper motor neuron paraparesis seen in chronic ingestion of inadequately cooked casava
Cyanide toxicity
Blister chemical agents 
Chlorate toxicity
Lewisite 
Sulfhemoglobinemia
Sulfur mustard 
Methemoglobinemia
Phosgene oxime 