Bothrops neuwiedi is a highly venomous pit viper species endemic to South America.

5°S, including Brazil (southern Maranhão, Piauí, Ceará, Bahia, Goiás, Mato Grosso, an isolated population in Amazonas, Rondônia and all southern states), Bolivia, Paraguay, Argentina (Catamarca, Córdoba, Corrientes, Chaco, Entre Ríos, Formosa, Jujuy, La Pampa, La Rioja, Mendoza, Misiones, Salta, San Juan, San Luis, Santa Fe, Santiago del Estero and Tucumán) and Uruguay.

[4] Bothrops neuwiedi is one of the main causes of snakebite in Argentina:[5] between 1960 and 1975, according to Esteso (1985), 80% of the approximately 500 cases reported each year were attributed to B. n.

[8] In a review of the symptoms in all 18 bite cases for this species admitted to the hospital in São Paulo between 1975 and 1992, Jorge and Ribeiro (2000) found all suffered pain, 83% had swelling, 50% had bruising, 17% had necrosis, 12% developed coagulopathy and 5% had abscesses, can also cause high blood pressure and collapse.

In a case in Germany, a 36-year-old snake keeper was bitten on the finger and developed hemorrhagic "necrosis" of the afflicted digit and swelling that extended onto the hand.

Five hours after being bitten, his blood had a normal platelet count, but was incoagulable with a reduced fibrinogen concentration, elevated fibrin degradation products and D-dimer.

Treatment with heparin might be beneficial in coagulopathy secondary to snake bite by reducing the circulating active thrombin.