Clinic: Bitis sp.

Examine for venom effects

Autopharmacological effects

• Nausea, vomiting
• Sweating
• Urticaria, angiooedema
• Arterial hypotension / hypovolaemic shock (transient, recurrent; immediate; delayed (CLS))
• Diarrhoea
• Bronchospasm 

Local Effects

• Pain
• Tender local (spreading) swelling
• Blistering
• Lymphangiopathy and lymphadenopathy
• Necrotic skin

Haematological effects 

• Clotting disturbances:
  • Bleeding from the fang marks and from injuries, in particular ones that are not located in the region in which venom application occurred.
  • Bleeding into the skin (ecchymosis, petechiae)
  • Gingival bleeding, bleeding from the nose, conjunctiva, haematemeis, bleeding per rectum, including melaena, haematuria, haemoptysis.
  • Oliguria, anuria (VICC / AKI)
• Bleeding and/or haemolytic anaemia:
  • Arterial hypotension (haemorrhagic shock)
  • Acute abdomen (intra-abdominal bleeding!)
  • Loin pain/renal bed sensitive to percussion (ischaemia, renal haemorrhage!)
  • Local neurological signs, meningism, coma (intracranial bleeding!)
  • Pale sclera (bleeding, haemolysis!)
  • Oliguria, anuria (arterial hypotension / AKI!)

Neurological effects

• Descending flaccid paralysis
  • Ptosis (not to be mixed up with tiredness / drowsiness; test: lid retraction with upward gaze).
  • Double vision (external ophthalmoplegia)
  • Difficulties to swallow (dysphagia) (bulbar paralysis) > inhalation of vomitus!
  • Difficulties to lift the head when lying on the back (‘broken neck syndrome’)
  • Cyanosis, shallow breathing, respiratory arrest (respiratory paralysis); respiratory arrest may be precipitated by obstruction of the upper airway by the paralysed tongue or inhaled vomitus. 
  • Weakness or loss of voluntary movement; movements of digits may still be possible, allowing the patient to communicate.
  • Loss of consciousness and generalized convulsions caused by hypoxaemia in patients who have respiratory paralysis.  

Cardiac Effects

• Bradycardia, tachycardia, arrhythmias
• Arterial hypotension
• Heart failure
• ECG:Tachyarrhythmias, sinus bradycardia, ST-T wave changes, varying degrees of atrioventricular block, and evidence of hyperkalaemia.

Renal effects

• Acute kidney injury:
  • Loin pain (lower back pain)
  • Renal bed sensitive to percussion
  • Haematuria, haemoglobinuria, myoglobinuria
  • Oliguria (< 400 ml of urine / 24 h), anuria
  • Uraemia (nausea, acidotic breathing, hiccups, pleuritic chest pain, encephalopathy) 

Species-specific envenoming pattern

The assessment of the envenoming pattern is based on the data from publication in which the identification of the snakes is clearly specified and in accordance with accepted criteria.

Regional variation in the envenomation pattern
¹Bitis arietans
“There is some regional variation in the pattern of envenoming; spontaneous bleeding, bruising and muco-cutaneous and serosal petechiae associated with thrombocytopenia in West Africa (Warrell et al. 1975), and frank coagulopathy in Uganda (Sezi et al. 1972), South Africa and elsewhere (Lavonas et al. 2002)” (Amr et al. 2020).

²Autopharmacological effects

B arietans

Vomiting, hypotension (Tianyi et al. 2025; Warrell et al. 1975).

Bitis atropos
Vomiting, abdominal pain (van der Walt and Muller 2019).

B. gabonica
Nausea, vomiting, angioneurotic oedema, tachycardia, arterial hypotension, pulmonary oedema, hypovolaemia and shock due to massive fluid loss into the tissue.From a pathophysiological perspective, a possible cause might be the autopharmacological release of endogenous mediators, e.g. release of bradykinin through kallikrein-like activity of the venom, a direct effect of venom components on vessel walls (haemorrhagins) which leads to increased vascular permeability and fluid sequestration in a region of extensive swelling (Marsh and Whaler 1984, McNally et al. 1993).

³Local effect

B arietans
Severe pain, progressive swelling, local bleeding, blisters, necrosis (Tianyi et al. 2025; Warrell et al. 1975).
Hypovolaemia is a common cause of hypotension resulting from local extravasation of plasma or blood leading to a massively swollen bitten limb, for example after envenoming by puff adders (Bitis arietans) in Africa and the Middle East (Warrell and Willimas 2023).
“Compartment syndromes may develop, especially involving the anterior tibial compartment after bites on the feet and ankles, leading to ischaemic necrosis of intra-compartmental muscles.” (Amr et al. 2020).

B. gabonica
Local pain, local swelling which spreads quickly and can extend to the trunk (a factor which can contribute to hypovolaemia and shock due to massive fluid loss into the tissue). Blistering in the area of the bite. Extensive ecchymoses in the region of the swelling. Frequently local tissue necrosis that can be severe (Marsh and Whaler 1984, McNally et al. 1993; Warrell and Willimas 2023).

Bitis atropos
Pain, swelling (van der Walt and Muller 2019). 

Hematological effects
⁴Bleeding
Systemic bleeding
Bitis arietans, Bitis gabonica, Bitis rhinoceros

Bitis arietans
“There is some regional variation in the pattern of envenoming; spontaneous bleeding, bruising and muco-cutaneous and serosal petechiae associated with thrombocytopenia in West Africa (Warrell et al. 1975), and frank coagulopathy in Uganda (Sezi et al. 1972), South Africa and elsewhere (Lavonas et al. 2002)” (Amr et al. 2020, Warrell et al. 1975).

⁵Coagulopathy

Type of haemostatic defect
Bitis arietans
“There is some regional variation in the pattern of envenoming; spontaneous bleeding, bruising and muco-cutaneous and serosal petechiae associated with thrombocytopenia in West Africa (Warrell et al. 1975), and frank coagulopathy in Uganda (Sezi et al. 1972), South Africa and elsewhere (Lavonas et al., 2002)” (Amr et al. 2020, Warrell et al. 1975).

B.gabonica, Bitis rhinoceros
Venom-Induced Consumption Coagulopathy with a strong anticoagulant effect. 

⁶Neurological effects

Bitis atropos
Disturbances in cranial nerve function (anosmia and altered taste, an ophthalmological triad of ptosis, mydriasis and visual disturbances including loss of accommodation, and dysphagia), and a global decrease in motor power with respiratory failure. Neurological signs and symptoms can be delayed for many hours (van der Walt and Muller 2019).

Other effects

Cardiotoxic effects?
Bitis arietans
“Myocardial damage and cardiac arrhythmias may contribute to hypotension, a cause of early deaths.” (Amr et al. 2020).

Renal effects
Bitis arietans
Acute kidney failure: among other factors direct nephrotoxic effect? (Warrell et al. 1975).

Hyponatraemia
Bitis atropos
Develops late, up to 1-2 days after the bite; lowest value recorded 111 mmol/L), sometimes with associated convulsions (van der Walt and Muller 2019, Warrell 2023, Warrell and Williams 2023). 

Species-specific publications: see ‘References’ at the end of the file. 

Clinical management

See also Clinical Management: Central and Southern Africa

for advice on post-First Aid measures, diagnosis (clinical, laboratory) and treatment (supportive, antivenom).

First Aid

Any type of tourniquet follow link above.

Local treatment

Pain control
Tetanus prophylaxis
Standard wound care
Necroses: debridement; split-thickness skin grafting
Systemic antibiotics: standard indications
WHO (2010a, 2010b) 

Systemic supportive treatment

A general understanding of emergency medicine is required, or can be found in emergency medicine guidelines, e.g. ABCDE approach, WHO-ICRC Basic Emergency Care.

Follow SAMPLE & ABCDE ApproAch

• Comprehensive ABCDE approach

• ICRC Basic Emergency Care: approach to the acutely ill and injured (SAMPLE  and ABCDE approach: first module) 

Obey bitis sp. - specific features

see

• 'Species-specific envenoming pattern above'.

and

• Guidelines for the Prevention and Clinical Management of snakebite in Africa

• National Snakebite Management Guidelines (2021) WHO Eswatini, Eswatini Antivenom Foundation

Key issues:

Hypotension and shock
Bitis arietans, Bitis gabonica, Bitis rhinoceros
A fall in blood pressure is a feature of  envenoming by theses species. Sinus tachycardia, orthostatic hypotension, suggests hypovolaemia resulting from extravasation into the tissues of the bitten limb or systemically, external haemorrhage, or generalized increase in capillary permeability (haemoconcentration). (Warrell 2023, Warrell et al. 1975).

Hyponatraemia 
Bitis atropos
Correction of Hyponatraemia (van der Walt and Muller 2019; Warrell 2023, Warrell and Williams 2023).

Systemic bleeding
Bitis arietans, Bitis gabonica, Bitis rhinoceros.

Respiratory failure
Bitis atropos
Lifesaving in neurotoxic envenoming:
Airway management
Breathing: Oxygen ⇨ assisted ventilation ⇨ mechanical ventilation

Acute kidney injury (AKI), chronic kidney disease
B arietans
Acute kidney failure: among other factors direct nephrotoxic effect? (Warrell et al. 1975).
“Envenoming by many snake species occasionally results in acute kidney injury, but Russell’s vipers are the most dangerous. Acute kidney injury is the major cause of mortality and morbidity among people who have been bitten by these species. Direct venom nephrotoxicity, renal ischaemia secondary to shock, disseminated intravascular coagulation with thrombotic microangiopathy (TMA), haemoglobinuria, myoglobinuria, and hyperkalaemia contribute to acute tubular necrosis.” (Warrell and Williams 2023)

Specific treatment (antivenoms)

• WHO Snakebite Information and Data Platform

• Guidelines for the Prevention and Clinical Management of snakebite in Africa

• National Snakebite Management Guidelines (2021) WHO Eswatini, Eswatini Antivenom Foundation
• World Health Organization(2023). Target product profiles for animal plasma-derived antivenoms: antivenoms for treatment of snakebite envenoming in sub-Saharan Africa

References

• Amr ZS, Abu Baker MA, Warrell DA.Terrestrial venomous snakes and snakebites in the Arab countries of the Middle East. Toxicon. 2020 Apr 15;177:1-15. doi: 10.1016/j.toxicon.2020.01.012. Epub 2020 Jan 27. PMID: 32001320. https://doi.org/10.1016/j.toxicon.2020.01.012
• Edwards, I. R., J. B. M. Fleming, M. F. M. James (1979) Management of a Gaboon viper bite: a case report. Centr. Afr. J. Med. 25: 217-221
• Lavonas EJ, Tomaszewski CA, Ford MD, Rouse AM, Kerns WP 2nd. Severe puff adder (Bitis arietans) envenomation with coagulopathy. J Toxicol Clin Toxicol. 2002;40(7):911-8. PMID: 12507061. https://doi.org/10.1081/clt-120016963
• Marsh NA, Whaler BC. The Gaboon viper (Bitis gabonica): its biology, venom components and toxinology. Toxicon. 1984;22(5):669-94. PMID: 6395443. https://doi.org/10.1016/0041-0101(84)90152-1
• McNally T, Conway GS, Jackson L, Theakston RD, Marsh NA, Warrell DA, Young L, Mackie IJ, Machin SJ. Accidental envenoming by a Gaboon viper (Bitis gabonica): the haemostatic disturbances observed and investigation of in vitro haemostatic properties of whole venom. Trans R Soc Trop Med Hyg. 1993 Jan-Feb;87(1):66-70. PMID: 8465400. https://doi.org/10.1016/0035-9203(93)90427-r
• National Snakebite Management Guidelines Kingdom of Eswatini 2021 https://eswatiniantivenom.org/newsite/wp-content/uploads/2021/12/WHO-Snake-Bite-Treatment-Protocol-Manuscript-A4.pdf 
• Phillips LL, Weiss HJ, Pessar L, Christy NP. Effects of puff adder venom on the coagulation mechanism. I. In vivo. Toxicon. 1973 Aug;11(5):423-31. PMID: 4755095. https://doi.org/10.1016/0041-0101(73)90118-9
• Sezi, C.L., Alpidovsky, V.K., Reeve, M.I., 1972. Defibrination syndrome after snake bite.East Afr. Med. J. 49 (8), 589–596.
• Tianyi FL, Ngari C, Wilkinson M, Parkurito S, Chebet E, Mumo E, Trelfa A, Otundo D, Crittenden E, Kephah GM, Harrison RA, Stienstra Y, Casewell NR, Lalloo DG, Oluoch GO. Clinical features of puff adder envenoming: case series of Bitis arietans snakebites in Kenya and a scoping review of the literature.PLoS Negl Trop Dis. 2025 Feb 10;19(2):e0012845. PMID: 39928662; PMCID: PMC11828387. https://doi.org/10.1371/journal.pntd.0012845
• van der Walt AJ, Muller GJ.Berg adder (Bitis atropos) envenoming: an analysis of 14 cases. Clin Toxicol (Phila). 2019 Feb;57(2):131-136Epub 2018 Dec 6. PMID: 30522357. https://doi.org/10.1080/15563650.2018.1499931
• Warrell DA. Venomous and poisonous animals.In: Farrar J, Garcia PJ, Hotez T, Junghanss T, Kang G, Laloo D (eds.). Manson’s tropical diseases. 24th ed. Elsevier; 2023.
• Warrell DA, Williams DJ. Clinical aspects of snakebite envenoming and its treatment in low-resource settings. Lancet. 2023 Apr 22;401(10385):1382-1398. PMID: 36931290. https://doi.org/10.1016/s0140-6736(23)00002-8
• Warrell DA, Ormerod LD, Davidson NM. Bites by puff-adder (Bitis arietans) in Nigeria, and value of antivenom. Br Med J. 1975 Dec 20;4(5998):697-700. PMID: 1203728; PMCID: PMC1675831. https://doi.org/10.1136/bmj.4.5998.697
• WHO (2010a) Guidelines for the prevention and clinical management of snakebite in Africa. https://www.who.int/publications/i/item/9789290231684
• WHO (2010b) Wound and lymphoedema management. WHO/HTM/NTD/GBUI/20101 I. 2010. https://www.who.int/publications/i/item/9789241599139
• WHO-ICRC Basic Emergency Care: approach to the acutely ill and injured (2018)  https://www.who.int/publications-detail-redirect/basic-emergency-care-approach-to-the-acutely-ill-and-injured
• WHO ABCDE Approach  https://cdn.who.int/media/docs/default-source/integrated-health-services-(ihs)/csy/bec-quick-cards/becp-edu29-pdf-en-finl.pdf?sfvrsn=2532d61b_2
• WHO Snakebite Information and Data Platform  https://www.who.int/teams/control-of-neglected-tropical-diseases/snakebite-envenoming/snakebite-information-and-data-platform

 Species-specific evidence

Bitis arietans

Kenya

Case series and review

• Tianyi et al. (2025)
  15 cases from two hospitals in Kenya. Identification: 1/15 snakes was killed and  brought dead to the hopital. 1/15 picture of the killed snake, 1 patient recognized the killed snake from photos of the medically important snakes in Kenya he was shown. 12/15 were identified on the basis of the description of the biting snake and recognition of the snake on a picture chart of the medically important snakes in Kenya.
  37 cases (!) reported since 1970 in the literature. Few studies reported coagulation parameters and even fewer serial test results!

Nigeria

• Warrell et al. (1975)
  Case series
  10 B. arietans bites; identification: morphological (8/10) or immunological with ELISA (Greenwood et al. 1974) (2/10).
  Classification:
  Local envenoming 10/10
  Extent of the swelling (grade 1–6; scale of Warrell et al. 1974)
  Grade 1: 2/10
  Grade 2: 1/10
  Grade 3: 1/10
  Grade 5: 4/10
  Grade 6: 2/10
  Intensity of the swelling (according to the method of Reid et al. 1963c): difference in circumference between the bitten extremity and the healthy extremity up to 28%.
  Systemic envenoming 4/10
  Criteria: spontaneous bleeding with thrombopaenia, hypotension, bradycardia.

Uganda

• Sezi et al. (1972)
  Cited in: Amr, Abu Baker, (Warrell 2020): “There is some regional variation in the pattern of envenoming; spontaneous bleeding, bruising and muco-cutaneous and serosal petechiae associated with thrombocytopenia in West Africa, and frank coagulopathy in Uganda (Sezi et al., 1972), South Africa and elsewhere”.

South Africa

• Visser and Chapman (1978)
  9 B. arietans bites that ended fatally.

Captive snake

• Husain et al. (2023)
  1 case
• Lavonas et al. (2002) 
  1 patient
• Phillips et al. (1973)
  1 patient

Signs & symptoms

Autopharmacological effects
Vomiting 2/10 (Warrell et al. 1975).
Arterial hypotension 3/10 (Warrell et al. 1975). Arterial hypotension caused by increased vascular permeability and vasodilatation, among other factors.
Arterila hypotension (Lavonas et al. 2002).
2/10 (Warrell et al. 1975). Principal causes of death acute and prolonged hypotensive state without significant blood loss, blood loss (Warrell et al. 1975).
All 9 fatal cases described by Visser and Chapman (1978) were in a state of hypovolaemic shock.

Local effects
Local pain 10/10 within 10 min after the bite (Warrell et al. 1975).
Local swelling 10/10 within 20 min after the bite, at the latest after 1–2 days, swelling disappeared after 5 days–3 weeks (Warrell et al. 1975).
Local blistering 5/10; necrosis 3/10, 17 h, 48 h and 7 days after the bite, respectively (Warrell et al. 1975).
Ecchymosis (on the bitten extremity) 2/10 (Warrell et al. 1975).
Thrombosis of the popliteal artery 1/10 (Warrell et al. 1975).
Extensive tissue defects and chronic ulceration of neglected wounds (necrosis) (Warrell et al. 1975).
Severe swelling, local tiossue necrosis) (Levonas et al. 2002).

Haemostatic effects
Spontaneous systemic bleeding 3/10: gingival bleeding (1/3) 4 h after the bite, epistaxis (2/3) days after the bite (Warrell et al. 1975).
Haemorrhage ((Levonas et al. 2002).

Cardiac effects
Hypotension, bradycardia: among other factors direct myocardial effect of the venom? (Warrell et al. 1975).

Renal effects
Acute kidney failure 1/10: among other factors direct nephrotoxic effect? (Warrell et al. 1975).

Laboratory investigations
Coagulation-activating/fibrinolytic effects probably not very marked in humans (Nigeria*; Warrell et al. 1975).
"A 22-year-old man bitten on the finger by a young puff adder (Bitis arietans) showed within 2 hr a slightly low platelet count, a slightly prolonged prothrombin time and a short euglobulin lysis time. Partial thromboplastin times (PTT) were accelerated." (Phillips et al. 1973).
Severe coagulopathy with marked abnormality in PT, PTT and figrinogen 4.5 hrs after the bite which resonded does-dependendly to antivenom administration. Thrombocytopaenia. D-Dimer less than 1.0 μg/mL 4.5. and 12 hrs after the bite (Lavonas et al. 2002).
*“There is some regional variation in the pattern of envenoming; spontaneous bleeding, bruising and muco-cutaneous and serosal petechiae associated with thrombocytopenia in West Africa (Warrell et al. 1975), and frank coagulopathy in Uganda (Sezi et al., 1972), South Africa and elsewhere (Lavonas et al., 2002)” (Amr et al. 2020, Warrell et al. 1975).

Bitis atropos

South Africa

• van der Walt and Muller (2019)
  14 patients

 Signs & symptoms

Autopharmacological effects
Vomiting (van der Walt and Muller 2019).

Local effects
Pain, swelling (van der Walt and Muller 2019).

Neurological effects
Cranial nerves (ansomnia, altered taste, ptosis, mydriasis, loss of accomodation, dysphagia), paralysis including repiratory muscles.

Other
Hyponatraemia (lowest value 11 mmol/L) associated with convulsions (van der Walt and Muller 2019).

Bitis gabonica (Eastern Gabon viper) / Bitis rhinoceros (Western Gabon viper)

Captive snakes

Bitis gabonica (Eastern Gabon viper)

• Marsh et al. (2007)
  4 patients
•  McNally et al. (1993)
  1 patient

Bitis rhinoceros (Western Gabon viper)

• St Francis et al. (2024)
  1 patient

Bitis gabonica or Bitis rhinocerus?

• Edwards et al. (1979)
  1 patient

Signs & symptoms

Autopharmacological effects
Nausea (McNally et al. 1993).
Pulmonary oedema (McNally et al. 1993)

Local effects

Pain, extended swelling (Marsh et al. 2007, McNally et al. 1993, St Francis et al. 2024). Extended sweeling with secondary haemoconcetratioan and hypovolaemia (McNally et al. 1993).

Necrosis of the skin (McNally et al. 1993).

Haematological effects
Bleeding (Marsh et al. 2007).

Laboratory investigations
Low fibrinogen and increased FDP levels; prolongied Prothombin time; platelet count probably not devreased due to early antivenmom treatment (Marsh et al. 2007; McNally et al. 1993).
Recurrence of haeomstatic disturbance at day 3 with initially normal haemostatic investigations (antivenom was given early after the bite) (McNally et al. 1993).
Thrombocytopaenia (St Francis et al. 2024).

References

• Amr ZS, Abu Baker MA, Warrell DA.Terrestrial venomous snakes and snakebites in the Arab countries of the Middle East. Toxicon. 2020 Apr 15;177:1-15. doi: 10.1016/j.toxicon.2020.01.012. Epub 2020 Jan 27. PMID: 32001320. https://doi.org/10.1016/j.toxicon.2020.01.012
• Edwards, I. R., J. B. M. Fleming, M. F. M. James (1979) Management of a Gaboon viper bite: a case report. Centr. Afr. J. Med. 25: 217-221
• Husain Z, Wicaksono AC, Renault A, Md Zhahir SS, Ismail AK. A case of fatal envenomation by a captive puff adder (Bitis arietans) in Malaysia. Toxicon. 2023 Mar 1;224:107023. Epub 2023 Jan 11. PMID: 36640813. https://doi.org/10.1016/j.toxicon.2023.107023
• Lavonas EJ, Tomaszewski CA, Ford MD, Rouse AM, Kerns WP 2nd. Severe puff adder (Bitis arietans) envenomation with coagulopathy. J Toxicol Clin Toxicol. 2002;40(7):911-8. PMID: 12507061. https://doi.org/10.1081/clt-120016963
• Marsh N, DeRoos F, Touger M. Gaboon viper (Bitis gabonica) envenomation resulting from captive specimens--a review of five cases. Clin Toxicol (Phila). 2007;45(1):60-4. PMID: 17357384. https://doi.org/10.1080/15563650600795693
• McNally T, Conway GS, Jackson L, Theakston RD, Marsh NA, Warrell DA, Young L, Mackie IJ, Machin SJ. Accidental envenoming by a Gaboon viper (Bitis gabonica): the haemostatic disturbances observed and investigation of in vitro haemostatic properties of whole venom. Trans R Soc Trop Med Hyg. 1993 Jan-Feb;87(1):66-70. PMID: 8465400. https://doi.org/10.1016/0035-9203(93)90427-r
• Phillips LL, Weiss HJ, Pessar L, Christy NP. Effects of puff adder venom on the coagulation mechanism. I. In vivo. Toxicon. 1973 Aug;11(5):423-31. PMID: 4755095. 
• Sezi, C.L., Alpidovsky, V.K., Reeve, M.I., 1972. Defibrination syndrome after snake bite. East Afr. Med. J. 49 (8), 589–596.
• St Francis H, Vaid RA, Rothenberg R, Hoffman RS, Mahonski SG, Calleo VJ, Biary R, Taylor CE, Silverberg JZ.A case of Western Gaboon viper (Bitis rhinoceros) envenomation: Successful treatment with South African Institute for Medical Research (SAIMR) antivenom after North American crotalid antivenom failure. Toxicon. 2024 Nov 6;250:108108. doi: 10.1016/j.toxicon.2024.108108. Epub 2024 Sep 27. PMID: 39343150.
• Tianyi FL, Ngari C, Wilkinson M, Parkurito S, Chebet E, Mumo E, Trelfa A, Otundo D, Crittenden E, Kephah GM, Harrison RA, Stienstra Y, Casewell NR, Lalloo DG, Oluoch GO. Clinical features of puff adder envenoming: case series of Bitis arietans snakebites in Kenya and a scoping review of the literature.PLoS Negl Trop Dis. 2025 Feb 10;19(2):e0012845. PMID: 39928662; PMCID: PMC11828387. https://doi.org/10.1371/journal.pntd.0012845
• van der Walt AJ, Muller GJ.Berg adder (Bitis atropos) envenoming: an analysis of 14 cases. Clin Toxicol (Phila). 2019 Feb;57(2):131-136Epub 2018 Dec 6. PMID: 30522357. https://doi.org/10.1080/15563650.2018.1499931
• Visser, J., D. S. Chapman (1978) Snakes and snake bite. Venomous snakes and management of snake bite in Southern Africa. Purnell, Cape Town: 152
• Warrell DA, Ormerod LD, Davidson NM. Bites by puff-adder (Bitis arietans) in Nigeria, and value of antivenom. Br Med J. 1975 Dec 20;4(5998):697-700. PMID: 1203728; PMCID: PMC1675831. https://doi.org/10.1136/bmj.4.5998.697