Mojave Rattlesnake Envenomation Clinical Presentation

Updated: Jun 25, 2015
  • Author: Sean P Bush, MD, FACEP; Chief Editor: Joe Alcock, MD, MS  more...
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In some cases, it may be helpful to know where the bite occurred (geographically) and whether venom A populations are known to occur in the area. [10]  Findings may include the following:

  • Pain around the bite site
  • Redness around the bite site
  • Swelling (which may be less with Venom A Mojave rattlesnakes)
  • Nausea, vomiting, or diarrhea
  • Difficulty breathing
  • Chest pain
  • Weakness
  • Paresthesias
  • Syncope, near syncope


Findings may include the following:

  • Fang marks (See the image below.)
    This is the typical appearance of a southern Calif This is the typical appearance of a southern California Mojave rattlesnake bite site. Photo by Sean Bush, MD.
  • Edema and erythema (Generally, local tissue effects are much less pronounced than typically observed after rattlesnake envenomation.)
  • Tenderness surrounding bite site
  • Tachycardia
  • Hypotension/shock
  • Myokymia (muscle movement, fasciculations)

Neurologic effects include the following:

  • Cranial nerve palsies
  • Ptosis
  • Diplopia
  • Dysphagia
  • Dysphonia
  • Motor weakness (severe, generalized)
  • Respiratory paralysis
  • Lethargy


A large percentage of bites occur when the snake is handled, kept as a pet, or abused. These bites are considered intentionally interactive.