1. INSECT BITES , STINGS
AND SNAKE BITES
(ENVENOMATION)

2. • ENVENOMATION
• VENOM
• LOCAL EFFECTS OF VENOM include pain,
swelling, erythema, bleeding, bruising,
blistering, and local tissue necrosis.
• SYSTEMIC EFFECTS LIKE
NEUROTOXICITY- flaccid paralysis

3. • Neurotoxic paralysis
• ‘Sleepy’ or drooping eyelids
• Difficulty swallowing, dysarthria and drooling
• Limb weakness and paralysis
• Respiratory distress and failure

4. ptosis
• For neurotoxic snakes, the cranial nerves are
usually involved first, with ptosis a common
initial sign

5. • Excitatory neurotoxicity (autonomic storm)
• Sweating, salivation
• Tingling around mouth, tongue or
• muscle twitching
• Dyspnoea (pulmonary oedema)

6. MYOTOXICITY muscle pain and tenderness.
CARDIOTOXICITY- affects myocardial contractility
COAGULOPATHY
RENAL DAMAGE
• NON SPECIFIC SYSTEMIC EFFECTS are
– Headache
– Nausea, vomiting, diarrhea
– Abd. Pain
– Bradycardia or tachycardia
– Dizziness, collapse or convulsions
– Shock or cardiac arrest

7. MANAGEMENT
 FIRST AID
• Immobilization
• Pressure bandage
• Reassurance
• Cardiorespiratory support- to support vital systems
 DIAGNOSIS
• History
• Examination
• Laboratory findings -full blood count, coagulation profile,
urea and electrolytes, creatinine, CK and ECG.
• Lung function tests, pulse-oximetry or arterial blood gases

8. TREATMENT
 ANTIVENOM
 SUPPORTIVE TREATMENT OF ORGAN
DYSFUNCTION
 ANTIBIOTICS
 TETANUS PROPHYLAXIS
 ANALGESICS

9. SPIDER BITES
• VENOM – causes local necrosis of skin and
tissues with some systemic toxicity.
• Most spider bites are painful but harmless.
except fiddle spiders or widow spiders can be
life threatening.
• Recluse spiders- severe tissue necrosis
• Widow spiders- neurotoxic

10. CLINICAL FEATURES
• most bites produce sharp pin prick pain at the
site of bite, with erythema and edema.
• The site becomes painful and pruritic with central
induration
• The lesion resolves in few days
• In severe cases the erythema spreads, centre of
lesion becomes hemorrhagic and necrotic with an
overlying bulla.
• Later there is sloughing of the necrotic tissue with
ulcer formation and a depressed scar.

11. • Severe tissue necrosis with systemic hemolysis
is seen with recluse spider bites.
• Abdominal muscles rigidity with muscle
cramps in trunk and extremeties is seen with
widow spider bites
• Other s/s N, V, increased salivation, myalgia,
tachycardia, fever, chills,weakness
• Rarely can cause cardiorespiratory arrest,
renal failure , or cerebral h’ge and death

12. TREATMENT
• R - rest
• I – ice
• C - compression
• E – elevation
• Analgesics and antihistaminics
• Tetanus prophylaxis
• antibiotics

13. SCORPION STINGS
• VENOM- local effect
- neurotoxic effect
• Bark scorpion produces venom that can be lethal in
humans
Clinical features
• Sharp burning pain and discoloration at the site with
little swelling
• Paresthesia- sensation of burning, pricking , itching or
tingling
• Hyperesthesia (tap test)

14. • Cranial nerves dysfunction
• Hyper-excitability of skeletal muscles, muscle twitching
and jerky movements
• Restlessness
• Blurred vision, abnormal eye movements, drowsiness
• Increased salivation, lacrimation, rhinorrhea
• Slurred speech
• C/C – HT, cardiac arrhythmias, hyperthermia, fatal
respiratory arrest

15. TREATMENT
• Aggressive supportive care
• Ice packs
• Pressure dressings
• Analgesics
• Antihistaminics
• IV midazolam infusion to control agitation and
involuntary ms movements
• antivenom

16. BEES AND WASPS STINGS
• Venom has direct toxic effects
• Clinical features include immediate sharp pain,
wheal and flare reaction with local edema.
• Multiple stings can lead to vomiting, diarrhea,
laryngeal edema, dyspnea, hypotension and
collapse.
• Sometimes severe anaphylaxis is seen,
characterized by nausea, abdominal cramps,
generalized urticaria, flushing, with upper airway
edema, bronchospasm, hypotension and shock
leading to death

17. TREATMENT
• Honeybee stinger should be removed from the skin
• Site cleansed and disinfected
• Ice pack
• Elevation
• Analgesics, antihistaminics
• topical calamine lotion
• Patients with multiple bee stings should be monitored
for evidence of renal failure or coagulopathy
• Anaphylaxis – Iv adrenalin 0.5ml in 1:1000 dilution,
with bronchodilators, O2, and intubation.

18. SNAKE BITES
• Viperids – viper, pit vipers, russell’s viper
• Elapids – cobras, kraits, coral snakes
• VENOM
• Viperids venom – bleeding and clotting
disturbances
• Elapids – neurotoxic venom

19. Snake venom
• Hemorrhagins –affects coagulation pathway -
vascular leakage and bleeding
• Proteolytic enzymes – local tissue necrosis
• Cardiotoxic
• Neurotoxic
Signs and symptoms
• Pain, progressive local swelling, ecchymosis and
hemorrhagic bullae

21. Severe tissue necrosis

22. Systemic findings
• Hypotension
• Bradycardia or tachycardia
• Pulmonary edema
• Hemorrhage
• Rhabdomyolysis
• Renal dysfunction
Neurologic symptoms
• Cranial N weakness leading to ptosis, mouth
numbness
• Severe envenomation can lead to muscle
paralysis, respiratory paralysis and death

23. Evaluation of the envenomed patient
• Taking a proper history
• Local effects and bite marks
• Symptoms and signs
• Investigations - CBC, ECG, RFT, LFT,
Coagulation studies, ABG, Urine for Blood
• Assessment of type and extent of
envenoming.

24. MANAGEMENT OF SNAKE BITE
1. First Aid – Immobilization of the bitten limb and elevation.
2. Pressure Bandage
3. Cardio Respiratory Support (ABC)
4. Endotracheal intubation and ventilatory support
5. Maintaining Vitals
6. Watch for cardiac rhythm, O2 saturation and urine output
7. IV Line
8. Vasopressors
9. Determine the severity of envenomation
10. antivenom
11. Measure the circumference of the bitten limb every 15 min
until the swelling stabilizes
12. Tetanus prophylaxis and antibiotics.

25. THANK YOU