Mojave Rattlesnake Envenomation Clinical Presentation

Updated: Apr 09, 2021
  • Author: Sean P Bush, MD, FACEP; Chief Editor: Joe Alcock, MD, MS  more...
  • Print


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. [12]  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


Physical Examination

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



Complications can include rhabdomyolysis, infection, respiratory difficulty, and death (rare).