Polyvalent Lonomia antivenom !
Antivenom from Colombia's INS against the venom of Lonomia caterpillars (churruscos), which causes a bleeding syndrome.
Updated 2026-11-01
Also called: Anti-Lonomia serum, Lonomic antivenom
Mechanism of action
Venom enters through the caterpillar's bristles on skin contact. It activates clotting and fibrinolysis, consumes fibrinogen and other factors, and causes bleeding hours after contact: bruising, gum bleeding, haematuria and, in severe cases, intracranial haemorrhage or kidney failure. Antibodies neutralise circulating toxins; response is followed with clotting tests.
- Caterpillar bristles inject venom into the skin
- Toxins activate clotting and fibrinolysis and consume fibrinogen
- Antivenom neutralises the circulating toxins
- Clotting tests normalise and bleeding stops
Pharmacokinetics
- Distribution
- Intravenous, in the plasma where the toxins circulate
Indications
- Contact with Lonomia caterpillars (L. casanarensis, L. orientoandensis) with abnormal clotting or bleeding
Adverse effects
Common
- Urticaria, itching and fever during the infusion
Contraindications
- No absolute contraindication in a Lonomia bleeding syndrome; anaphylaxis treatment is prepared
Key interactions
- Antifibrinolytics
- Used before antivenom existed; today antivenom is the treatment of choice
What is monitored
- Fibrinogen and clotting times before and after antivenom
- Bleeding from gums, urine, gut and neurological signs
- Kidney function
Administration and safety
- Intravenous only, under medical supervision
- Store refrigerated (2–8 °C)
- Have anaphylaxis treatment ready
Nursing care
- Ask about caterpillar contact even if the skin lesion looks mild
- Watch for signs of bleeding and urine output
- Take the clotting samples requested before and after antivenom
- Watch for reactions during the infusion
Pregnancy and breastfeeding
The bleeding syndrome endangers mother and fetus; pregnancy does not prevent antivenom when it is indicated.
Test yourself
Think of the answer, then tap the question to see it.
What syndrome follows contact with Lonomia caterpillars?
A bleeding syndrome from consumption of fibrinogen and other factors and intense fibrinolysis, appearing hours after contact.
How is the response to Lonomia antivenom assessed?
With clotting tests (fibrinogen and clotting times), which should improve.
Which kidney complication can accompany Lonomia envenoming?
Acute kidney failure, as a complication of the bleeding disorder.
Related drugs
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Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: Venta de Antivenenos (Instituto Nacional de Salud (Colombia), 2026); Síndrome hemorrágico por contacto con orugas del género Lonomia (Saturniidae) en Casanare, Colombia: informe de dos casos (Biomédica (Instituto Nacional de Salud, Colombia), 2001); Guidelines for the production, control and regulation of snake antivenom immunoglobulins, Annex 5, TRS No 1004 (World Health Organization, 2017).
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