Caterpillar Envenomation Treatment & Management
- Author: Robert L Norris, MD; Chief Editor: Scott H Plantz, MD, FAAEM more...
Prehospital Care
- The involved skin should be immediately washed with soap and water, and dried without contacting the skin (eg, use a hair dryer).
- Local cooling measures can be applied to reduce pain. This may be enhanced by applying topical isopropyl alcohol or ammonia.
- Following ocular exposure, the eyes should be irrigated immediately with copious water.
- Following dermal exposure to irritant or toxic hairs or setae of caterpillars or moths, sticky tape (especially duct tape) can be applied to the site in an effort to remove retained setae. Alternative effective methods of removal include use of rubber cement, clear fingernail polish, or facial peels (each applied, allowed to dry, then peeled away).
- If acute symptoms follow respiratory exposure, supportive care is in order as necessary, including oxygen, antihistamines, and beta-agonist inhalers, if available.
- Anaphylaxis should be treated in standard fashion.
- Following caterpillar stings, the extremity should be splinted and elevated, and ice should be applied to reduce pain.
- Any potentially constrictive jewelry should be removed before swelling progresses.
Emergency Department Care
- Wash the skin with soap and water as mentioned above if this has not already been done in the field.
- Ensure appropriate tetanus immunization status.
- Treat skin exposure as follows:
- Apply sticky adhesive tape (especially duct tape) to the site to remove all remaining hairs or spines possible. Other measures of removal as described previously for prehospital care can also be tried.
- Acute dermatitis can be treated with antihistamines (H1 and/or H2 blockers), although their efficacy is controversial. Additionally, topical steroids may be employed. Systemic steroids may be necessary in patients with severe or persistent cutaneous symptoms. Application of antipruritic products containing menthol may be soothing.
- Prostaglandin-synthetase inhibitors, such as aspirin or indomethacin, have been reported to reduce associated discomfort, but should be avoided if any evidence of coagulopathy is present.
- Treat respiratory exposure as follows:
- Symptoms can be managed with antihistamines (H1 and/or H2 blockers) and beta agonist aerosols/inhalers if wheezing is present.
- If significant symptoms occur, supplemental oxygen administration may be needed, and systemic steroids may be useful.
- Treat ocular exposure as follows:
- Instill a topical anesthetic and irrigate the eyes immediately with copious saline.
- Perform a slit lamp examination with fluorescein. The patient should receive close ophthalmologic follow-up care to rule out retained setae or hairs.
- Eye complications resulting from a retained migrating hair can be severe, and surgical removal may be necessary.
- Treat stings as follows:
- Management is primarily symptomatic and supportive. Splint and elevate the involved extremity; ice can be applied to reduce pain and swelling. Efforts, as outlined above, should be instituted to remove any retained spines or hairs.
- Narcotic analgesics may be required for pain relief. Anecdotal reports exist of the successful use of calcium gluconate (eg, 10 mL of a 10% solution by slow intravenous [IV] administration) to relieve muscle pain following M opercularis stings. Antihistamines (H1 and/or H2 blockers) may reduce concomitant pruritus.
- Treat rare cases of caterpillar or moth-related anaphylaxis in standard, aggressive fashion, including airway management, epinephrine, oxygen, antihistamines, steroids, IV fluids, and vasopressors as needed.
Consultations
- Consultations usually are not necessary following most caterpillar contacts.
- Ophthalmology may be needed for prompt consultation if ocular involvement is present.
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