← Back to the archive★ Support my pages
DD-598Naturealso ScienceFiled Last updated

Blood Destruction II

Short answer: Many snake venoms, especially those of vipers (the family that includes rattlesnakes), are haemotoxic: they act on blood and blood vessels. A 2017 review in the British Journal of Haematology by Slagboom and colleagues describes three main routes.

First, snake venom metalloproteinases (SVMPs) digest the basement membrane that supports capillary walls, especially type IV collagen. A 2016 review by Gutiérrez and colleagues explains that the weakened capillaries are then torn apart by the normal pressure of blood flow, so blood leaks into the tissue. Second, procoagulant toxins activate clotting factors such as Factor X and prothrombin, or act directly on fibrinogen. Inside the body this burns through the clotting factors, a condition called venom-induced consumption coagulopathy (VICC), and the blood ends up unable to clot. That's why a bite can cause both clotting and bleeding. Third, toxins such as disintegrins and C-type lectins can block platelets from clumping, or activate them until they're used up. Slagboom and colleagues cite about 1.8 million snake envenomings and up to 125,000 deaths a year. The same toxins are studied as drugs and diagnostic tools. The footage shows venom being collected from a snake held over a covered jar, then drawn into a syringe and added to blood in a glass, where the blood quickly thickens into a clot, a lab-glass illustration of the procoagulant effect. The snake isn't identified.

VideoWrite-up3 sources
More like this★ Support my pagesCite this file

What should you know about Blood Destruction II?

Quick facts. Each one stands alone and has a stable ID you can cite.

  1. Snake venom metalloproteinases break down capillary walls.

    DD-598-F01 · Write-up · Exhibit A (Vessel walls give way)

  2. Venom can clot blood and then leave it unable to clot.

    DD-598-F02 · Write-up · Exhibit A (Vessel walls give way)

Video transcript: Blood Destruction II: Venom That Unmakes Blood

DID YOU KNOW? Snake venom's impact on human blood is a striking biochemical process. Hemotoxic venoms, like those from rattlesnakes, disrupt blood clotting, causing uncontrolled bleeding or dangerous clots. The venom's enzymes break down vessel walls, leading to hemorrhage, while platelets fail to aggregate properly. NOW YOU KNOW!

Burned-in captions, read frame by frame (see transcript.md) · 16.4s Reel ·

Video coming soonBlood Destruction II · Instagram Reel
Blood Destruction II: Venom That Unmakes Blood Instagram Reel · · 16.4s

The write-up

Venom that unmakes blood. Viper venoms attack clotting, platelets and vessel walls.

  1. Exhibit A

    Vessel walls give way

    Metalloproteinases digest the capillary basement membrane, and blood pressure then tears the vessel open.

  2. Exhibit B

    Clots that cause bleeding

    Procoagulant toxins use up clotting factors, leaving blood that can no longer clot (VICC).

  3. Exhibit C

    Platelets disabled

    Disintegrins and other toxins block platelet clumping or use platelets up.

  4. Exhibit D

    Mostly vipers

    Most snakes known to cause VICC are vipers, the family that includes rattlesnakes.

  5. Exhibit E

    A global toll

    Slagboom and colleagues cite about 1.8 million envenomings and up to 125,000 deaths a year.

Questions people ask about Blood Destruction II

Which venom enzymes break down capillary walls?

Snake venom metalloproteinases (SVMPs).

Source: Write-up · Exhibit A (Vessel walls give way) · Gutiérrez et al. (2016): Hemorrhage caused by snake venom metalloproteinases: a journey of discovery and understanding, Toxins (PMC); Kini & Koh (2016): Metalloproteases affecting blood coagulation, fibrinolysis and platelet aggregation from snake venoms, Toxins (PMC)

What does VICC stand for?

Clotting factors get used up.

Source: Write-up · Exhibit B (Clots that cause bleeding) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC); Kini & Koh (2016): Metalloproteases affecting blood coagulation, fibrinolysis and platelet aggregation from snake venoms, Toxins (PMC)

Which protein runs low in VICC?

Leaving blood that can't clot.

Source: Write-up · Exhibit B (Clots that cause bleeding) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC); Kini & Koh (2016): Metalloproteases affecting blood coagulation, fibrinolysis and platelet aggregation from snake venoms, Toxins (PMC)

Which snake family causes most VICC cases?

Rattlesnakes are vipers.

Source: Write-up · Exhibit D (Mostly vipers) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC)

About how many snake envenomings happen each year, per the 2017 review?

With up to 125,000 deaths.

Source: Write-up · Exhibit E (A global toll) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC)

Test Your Knowledge

All quizzes →

5 questions, all from this case file. Answers are revealed instantly.

  1. Which venom enzymes break down capillary walls?

    1. Metalloproteinases
    2. Amylases
    3. Lipases
    4. Lactases
    Show the answer

    Answer: A. Metalloproteinases Snake venom metalloproteinases (SVMPs). Source: Write-up · Exhibit A (Vessel walls give way) · Gutiérrez et al. (2016): Hemorrhage caused by snake venom metalloproteinases: a journey of discovery and understanding, Toxins (PMC); Kini & Koh (2016): Metalloproteases affecting blood coagulation, fibrinolysis and platelet aggregation from snake venoms, Toxins (PMC)

  2. What does VICC stand for?

    1. Venom-induced consumption coagulopathy
    2. Viral infection of capillary cells
    3. Venous inflammatory clot complex
    4. Vascular injury from cold contact
    Show the answer

    Answer: A. Venom-induced consumption coagulopathy Clotting factors get used up. Source: Write-up · Exhibit B (Clots that cause bleeding) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC); Kini & Koh (2016): Metalloproteases affecting blood coagulation, fibrinolysis and platelet aggregation from snake venoms, Toxins (PMC)

  3. Which protein runs low in VICC?

    1. Fibrinogen
    2. Insulin
    3. Keratin
    4. Collagen in bone
    Show the answer

    Answer: A. Fibrinogen Leaving blood that can't clot. Source: Write-up · Exhibit B (Clots that cause bleeding) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC); Kini & Koh (2016): Metalloproteases affecting blood coagulation, fibrinolysis and platelet aggregation from snake venoms, Toxins (PMC)

  4. Which snake family causes most VICC cases?

    1. Vipers
    2. Boas
    3. Pythons
    4. Blind snakes
    Show the answer

    Answer: A. Vipers Rattlesnakes are vipers. Source: Write-up · Exhibit D (Mostly vipers) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC)

  5. About how many snake envenomings happen each year, per the 2017 review?

    1. 1.8 million
    2. 1,800
    3. 18,000
    4. 180 million
    Show the answer

    Answer: A. 1.8 million With up to 125,000 deaths. Source: Write-up · Exhibit E (A global toll) · Slagboom et al. (2017): Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise, British Journal of Haematology (PMC)

Cite this case file

Easterling, Marcus. "Blood Destruction II." The Detail Department (DetailEnjoyer), case file DD-598, last updated Jun 17, 2025. https://detailenjoyer.com/case/blood-destruction-ii/

Permalink: https://detailenjoyer.com/case/blood-destruction-ii/ · Last updated

Markdown version

Cite a single fact by its ID, for example DD-598-F01 → https://detailenjoyer.com/case/blood-destruction-ii/#DD-598-F01