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Puss Moth Caterpillar Stings

(Asp Stings)

By

Robert A. Barish

, MD, MBA, University of Illinois at Chicago;


Thomas Arnold

, MD, Department of Emergency Medicine, LSU Health Sciences Center Shreveport

Last full review/revision May 2020| Content last modified May 2020
Click here for the Professional Version

The venomous puss moth caterpillar (Megalopyge opercularis; also called the asp) is present in the southern United States. It is teardrop shaped and has long silky hair, making it resemble a tuft of cotton or fur.

When a puss moth caterpillar rubs or is pressed against a person’s skin, its venomous hairs are embedded, usually causing severe burning and a rash. Pain usually subsides in about an hour.

Occasionally, the reaction is more severe, causing swelling, nausea, and difficulty breathing.

Treatment of Puss Moth Caterpillar Stings

  • Relief of pain

Several techniques may soothe the pain and burning caused by puss moth caterpillar stings.

  • Washing the sting with soap and water and using a hair dryer set on low to dry the area

  • Putting tape on the site and pulling it off to remove embedded hairs to prevent further injury

  • Applying isopropyl alcohol (rubbing alcohol) to the sting

  • Applying a baking soda slurry

  • Applying calamine lotion

  • Placing an ice pack or an ice cube wrapped in plastic and a thin cloth over the sting

More severe reactions require immediate medical attention.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
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Fractures of the Jaw and Midface
Fractures to one or more facial structures can result from a single injury. Jaw fractures may occur to the mandible, or lower jaw, or to the maxilla, bone of the upper jaw. Other structures susceptible to fracture include the eye sockets, nose, and cheek bones. Which of the following facial structures is most likely to fracture if a person falls from a great height or hits the windshield of a car face-first during a motor vehicle accident?
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