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Guidance when the culprit has not been seen / not identified 

In most cases of scorpion stings, the scorpion has not been seen at all, has only been seen vaguely or has not been reliably identified.

The regional 'clinical management' section you accessed provides guidance in such cases.

Caution: do not attempt to capture scorpions if you are not trained to do so!

With scorpion stings, identification of the culprit is particularly difficult.

If the scorpion is not brought in for identification, identification on the basis of the patient's description is highly questionable. If the scorpion is available for identification, it is possible in most cases to achieve a conclusive result if identification is performed by an expert.

In many cases, clinical data from the literature cannot be related to a conclusively identified species. The available clinical information often comes from stings caused by various species of scorpion. It is possible that the individual specimens were identified reliably, identified according to unclear criteria, or not identified at all. Indirect criteria, such as the typical envenoming features for a particular species of scorpion and geographical location, are often used to aid identification.

Common features of medically important scorpion envenoming

Neurological effects

  • Neuromuscular and autonomic nervous system dysfunction (transient cholinergic effects and longer-lasting adrenergic effects) 
    The major systemic effects of envenoming are caused by endogenous catecholamines, which are released in response to the venom. As these are transmitters in the sympathetic, parasympathetic and somatic nervous systems, the resulting clinical symptoms of envenoming are dealt within the section "Neurological effects".
    Ryan et al. (2021), however, argue that “Akin to scorpion envenomation, the symptoms of IS cannot be wholly attributed to sympathetic hyperstimulation” citing Reis et al. (2019). “Also akin to scorpionism, generalised IS symptoms resemble those of CRS.”
    IS=Irukandji Syndrome; CRS=Cytokine Release Syndrome

Time course

Local effects

  • Within minutes: Local pain is the dominant symptom, often severe; redness; oedema; numbness.

Systemic effects

  • May develop within minutes but may be delayed for as much as 24 hours (Warrell 2023).
  • Monitoring of patients: at least 4 hours. Late deterioration up to 12 hours can occur (Maddy et al 2021; Wilkins et al 2025).
  • Observation up to 24 hours recommended by Warrell (2023).
  • Severe envenoming is more likely in children and pregnant women most commonly manifesting as hypertensive crisis (Wilkins et al 2025).

Species-specific hints directing towards the culprit of envenomation    

Immobilization of the stung limb

There is no evidence for the use of pressure-bandage immobilisation (Wilkins et al 2025).

Patient presents with a pressure bandage / pad but, also, tight (arterial) tourniquets (see comment below) on the affected extremity

Check venous and arterial blood supply in the extremity.

Comment 

Unfortunatelly, tight (arterial) tourniquets are still being applied. They must not be rcommended for general use. 

  • Since there is no evidence for the use of pressure-bandage immobilisation (Wilkins et al 2025) and, also, tight (arterial) tourniquets (see comment above), they can most likey be immediatelly removed.
  • Close observation afte removal is neverthess advisable.
  • Adverse outcomes have been observed in patients with tight tourniquets/pressure bandages left in place for many hours (Little 2023).

Is it likely that the patient is envenomned?

Inquire re

  • time of the sting,
  • nausea, vomiting.
  • Sting
    • Local pain is the dominant symptom, often severe
    • redness; oedema; numbness.
    • Tender local (spreading) swelling,
    • Blistering,
    • Lymphangiopathy and lymphadenopathy,
    • Necrotic soft tissue; can include muscle locally.

Assess

  • state of consciousness.

Measure

  • blood pressure/pulse,
  • breathing (respiratory rate),
  • oxygen saturation (pulse oximeter),
  • 20WBCT (bedside test) (see Nebo hierochonticus in: Clinical entries: Scorpions).

Observe/investigate

  • Sting area
    • Local pain,
    • Tender local (spreading) swelling,
    • Blistering,
    • Lymphangiopathy and lymphadenopathy,
    • Necrotic soft tissue; can include muscle locally.
  • Autonomic nervous system
    Within hours:
    Transient cholinergic effects
    Vomiting, increased peristalsis, diarrhoea, abdominal pain; profuse sweating; pupil constriction.Bradycardia, arterial hypotension, shock. Hypersalivation; increased bronchial secretion, bronchospasm, respiratory failure. Priapism.
    Longer-lasting adrenergic effects
    Pupil dilatation.
    Tachycardia, arrhythmia, sarterial hypertension, myocardial failure, pulmonary oedema (cardiogenic + ?non-cardiogenic component), cardiac ischaemia, shock.
    Hyperglycaemia (most likely due to hypercatecholaminaemia) 
    Acute pancreatitis (also associated with hyperglycaemia)
    Hypertensive encephalopathy. 
  • Clotting disturbances (see Nebo hierochonticus in:Clinical entries: Scorpions)
    Localizing neurological signs, meningism, coma (intracranial bleeding!)
    Systemic bleeding: retinal haemorrhages; cranial CT features of cerebellar and cerebral and cerebellar haemorrhages.

  • Microangiopathic haemolysis (see Hemiscorpius lepturus in:Clinical entries: Scorpions)
    Severe microangiopathic haemolysis causing early haemoglobinuria and leading to a HUS-like presentation with AKI that requires renal replacement therapy (Warrell 2023).

  • Neuromuscular dysfunction
    • Cranial nerves: Ptosis, "wandering" eye movements, dysphagia (inhalation of vomitus!), dysarthria, pharyngeal reflex absent;
    • Skeletal musculature: involuntary movements, restlessness, reduced grip and pinch strength; muscle spasms.
    • Descending flaccid paralysis(rarely progresses to involve respiratory muscles)
    • 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. 
    • Loss of consciousness and generalized convulsions caused by hypoxaemia in patients who have respiratory paralysis. 

Laboratory and physical investigations

Cardiovacsulas effects

  • Blood pressure, pulse
  • ECG
  • Chest X-ray
  • Blood gas analysis
  • Forced expiration test (peak expiratory flow)
  • Echocardiography and other forms of cardiac imaging

Haematological effects (Hemiscorpius lepturus - haemolysisNebo hierochonticus - coagulopathy): see 'Clinical entries: Scorpions'

  • Hb, Hct
  • Clotting time
  • PT/aPTT
  • TT
  • Fibrinogen
  • FSP
  • D-dimers
  • Platelets
  • Blood films (schistocytes > 1% is diagnostic of microangiopathic haemolytic anaemia) (early and late haemolysis obeserved!)
  • Free haemoglobin in the plasma and urine
  • Haptoglobin
  • Blood group/blood sample for cross-matching

Exclusion of a clinically relevant local and systemic envenoming

Monitoring for signs and symptoms of local and systemic envenoming (see above).

Symptomatic emergency medical treatment and antivenom treatment are complementary strategies.

Symptomatic emergency medical treatment and antivenom treatment are complementary strategies.

Antivenom in those scorpion stings in which antivenom is avaibale, of proven value and indicated, it must be secured as early as possible while emergency medical treatment is running.

The aim of symptomatic emergency medical treatment is the rapid correction of critical parameters (fluid balance, blood pressure, oxygenation etc.) and the maintenance of vital functions (respiratory, cardiovascular).

Symptomatic measures help bridge the gap until specific treatment (antivenom) can be administered and starts being effective. If no antivenom is available or if the required effect is not achieved with antivenom, the goal is to employ symptomatic measures until such time as the venom naturally starts losing its activity.

The aim of antivenom treatment is neutralisation of the venom. The success of antivenom treatment depends on the quality of the antivenom, the specific properties of those venom components relevant to envenoming and the time point at which antivenom is administered (neurotoxic envenoming).

Who requires antivenom?

Indications see 'Clinical mangement', 'Antivenom' in 'Clinical entries: Scorpions'

See also
Emergency flowchart: Scorpions

Clinical flowchart: Scorpions

How is the appropriate antivenom chosen?

See

If the selected antivenom is not effective, 3 possible causes need to be considered

  1. correct identification of the cause, but insufficient dose administered;
  2. correct identification of the cause, but inadequate efficacy of the antivenom;
  3. incorrect identification of the cause → revision of identification.

Early antivenom treatment is recommended, however, supportive evidence is poor (Amr et al. 2021; Wilkins et al. 2025, Warrell 2023).
Two systematic reviews and metanalyses performed in 2011 and 2017 found only for Centruroides spp. in Mexico and USA (Boyer et al. 2009) and Hottentotta tamulus in India (more rapid resolution than prazosin alone; Natu et al. 2010; Bawaskar and Bawaskar 2011) limited evidence of faster resolution of signs and symptoms of envenoming (Abrough et al. 2011; Rodrigo et al. 2017).
In a trial in Tunesia (patients likely to have been stung by Androctonus australis or Buthus occitanus) antivenom did not show a benefit. However, only 18% of patients were envenomed (Abrough et al. 1999; Amr et al. 2021).

Indication and selection of antivenom needs to be based on the evidence available in the respective region where the envenoming occurs.

How are antivenoms administered and complications treated?

See 

Monitoring of the patient after administration of antivenom

Repeat clinical examination (as above) with those clinical and laboratory parameters which were decisive for the indication of applying the antivenom.

Complications

See 

General supportive emergency medical 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.

Species-specific clinical envenoming patterns and clinical management  

see

  • 'Species-specific envenoming patterns'

and

  • 'Clinical mangement'

in

'Clinical entries: Scorpions

  

  

Local effects1
 

Haemato-
logical
effects

Neurological effects2
Neuromuscular and autonomic nervous system dysfunction
Androctonus sp.A      
Buthus sp.B       
Centruroides sp.C      
Hemiscorpius lepturusD      
Hottentotta thamulusE      
Leiurus sp.F      
Nebo hierochonticusG      
Parabuthus sp.H       
Tityus sp.I