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  1. Terrestrial snakes
  2. South America and the West Indies
  3. Clinical Flowchart

Clinical Flowchart

Autopharmacological effects

Bothrops sp.
Minutes 
           
Nausea, vomiting, abdominal pain, diarrhoea
(urticaria, angio-oedema)
(bronchospasm)
arterial hypotension
 
 Hypovolaemia/hypovolaemic shock
   
Cardiovascular failure

Local effects

Bothrops sp.
(Crotalus durissus ssp.1)
Lachesis sp.
Minutes (to hours)
   
Local pain and swelling
   
Painful swelling of the regional lymph nodes
                    
 Extensive swelling
 
Hypovolaemia
 
Necrosis
Loss of function of extremities
Loss of extremities		  
1 Local signs and symptoms can be minimal / absent

Haematological effects

Bothrops sp.1,2
Crotalus durissus ssp.
Lachesis sp.
< 1 hour to hours
    
Gingival bleeding
   
Bleeding from wounds remote from the site of the bite
 
Haematemesis, bleeding per rectum, haematuria
     
Systemic bleeding

Intracranial bleeding 
(focal neurological deficits, 
meningismus, coma)
 
Hypovolaemia/haemorrhagic shock
       
Cardiovascular failure Renal failure CNS failure
1 Bothrops atrox (Duarte et al. 2025, Warrell 2009), Bothrops erythromelas (Mota et al. 2020), Bothrops jararaca (Amaral et al. 1985, Bucaretchi et al. 2019, Malaque et al. 2019), Bothrops lanceolatus (Malbranque et al. 2008) envenoming can, addtionally, cause thrombotic micro-angiopathy (TMA). 
2

Bothrops lanceolatus 
“In situ arterial thrombosis (cerebral, pulmonary, coronary, etc.) is an important additional feature of envenoming by the ‘fer-de-lance’ (B. lanceolatus) of Martinique (Warrell 2023).

Neurological effects

Micrurus sp.
Crotalus durissus ssp.
Minutes to hours
 
Cranial nerve deficits (ptosis, ophthalmoplegia, dysphagia, dysarthria)
 
Paralysis of the skeletal musculature including the respiratory musculature
 
Respiratory failure
 

Lachesis sp. 

"Bushmaster (Lachesis spp.) envenoming causes a distinctive autonomic syndrome of sweating, repeated bilious vomiting, severe abdominal colic, profuse diarrhoea, hypotension, sinus bradycardia, and shock that can develop as early as 15 min after the bite.” (Warrell and Williams 2023).

Muscular effects

Crotalus durissus ssp.
Hours
 
Myalgia (at rest, with active/passive movement, upon pressure), dark urine, ECG changes
 
Signs of paralysis
 
Rhabdomyolysis

Cardiac effects

?1
1 “Cardiac alterations are not a frequent outcome but are highly linked to severe cases”. A range of mechanism can explain the pathogenesis of cardiac disorders in Bothrops envenoming one of which is a direct effect of venom components on the heart (B. atrox, Sartim et al. 2025). 

Renal effects

Crotalus durissus ssp.1
Bothrops sp.2
Hours to days
 
Flank pain, renal bed sensitive to percussion
 
Urinary output <400 ml/24 h
 
Renal failure
1 After Crotalus snakebite in South America, the most common complication is AKI due to rhabdomyolysis (Azevedo-Marques et al. 1985, 1987; Malaque and Gutiérrez 2017; Pinoh et al. 2005, 2008; Silveira and Nishioka 1992; Warrell 2004, 2023).
2 AKI results from a combination of factors, possibly including direct action of the venom (Malaque and Gutiérrez 2017; Pinho et al. 2008, Sitprija 2006; Warrell 2004, 2023).