eMedicine Specialties > Emergency Medicine > Environmental

Millipede Envenomation

Robert L Norris, MD, Associate Professor, Department of Surgery; Chief, Division of Emergency Medicine, Stanford University Medical Center

Updated: Apr 20, 2009

Introduction

Background

Millipedes are elongated cylindrical creatures that bear 2 pairs of legs per body segment and are found in a wide variety of habitats. They are generally very slow-moving creatures and are relatively innocuous. Falling into the class Diplopoda and the phylum Arthropoda, millipedes comprise some 7000 species.

The desert millipede, Orthoporus ornatus. Photo by Robert Norris, MD.

Millipede contact injury on day 3 following exposure.

Pathophysiology

Millipedes do not have biting mouthparts or fangs. Their medical importance comes from their ability to secrete an irritating defensive liquid from pores along their sides. Such secretions contain benzoquinones, aldehydes, hydrocyanic acid, phenols, terpenoids, nitroethylbenzenes, and other substances.

Some species are capable of squirting these liquids to distances of up to 25 cm.

Mortality/Morbidity

No deaths have been documented from millipede exposures, and it is unlikely that such an exposure could be fatal, even to a small child.

Clinical

History

The history may indicate that a patient was handling a millipede. On occasion, the history of a patient (eg, a sleeping victim, small child) may be obscure.

Skin irritation
Pain
Brown staining at the site of contact
Slight blistering
Eye irritation and pain

Physical

Local erythema
Mild edema
Vesicles
Occasionally, cracked skin that may slough and then heal
Conjunctivitis, which may lead to ulceration of the conjunctiva and cornea

Differential Diagnoses

Centipede Envenomations

Workup

Laboratory Studies

No lab studies are required.

Treatment

Prehospital Care

Any millepede secretions on the patient's skin should be washed away with soap and water.
If the eyes are involved, they should be copiously washed with water as soon as possible.

Emergency Department Care

The exposed skin should be washed thoroughly with soap and water.
Eye exposure should prompt immediate instillation of local anesthetic drops, followed by copious irrigation with saline solution or water.
Adequate tetanus immunization status should be ensured.
Topical steroid creams may be beneficial for local skin irritation.

Medication

Significant conjunctivitis or dermatitis caused by toxic millipede secretions can be treated with topical steroids.

Ophthalmic agents

These agents prevent further ulcerations of the cornea and should be given in consultation with an ophthalmologist.

Prednisolone, ophthalmic (Pred Forte)

Decreases inflammation by suppressing the migration of polymorphonuclear leukocytes and reversing increased capillary permeability.

Dosing

Adult

Solution: 1-2 gtt into conjunctival sac qh during day and q2h during night; once desired response is obtained, use 1 gtt q4h; may reduce to 1 gtt tid/qid to control symptoms
Suspension: Shake well before using, instill 1-2 gtt into conjunctival sac 2-4 times qd; may increase dosing frequency during initial 1-2 d prn

Pediatric

Administer as in adults

Interactions

None reported

Contraindications

Documented hypersensitivity; viral, fungal, or tubercular skin lesions

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Caution in hypertension; known to cause cataract formation with chronic use; in prolonged use, withdraw treatment by gradually decreasing frequency of applications to avoid adrenal insufficiency

Sulfacetamide sodium and prednisolone (Isopto)

Treats steroid-responsive inflammatory ocular conditions that have a risk of infection.

Dosing

Adult

Solution: Instill 1-3 gtt q2-3h while awake and hs until favorable response
Ointment: Apply 0.5-inch ribbon into lower conjunctival sac 1-4 times qd and once hs

Pediatric

<2 months: Not established
>2 months: Administer as in adults

Interactions

Decreases effects of silver compounds and gentamicin

Contraindications

Documented hypersensitivity; mycobacterial infection

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Caution in severe dried eyes; ointment may retard corneal epithelial healing

Corticosteroid, Topical

Used to treat erythema and skin irritation that result from chemical insults. Prevent further ulcerations of the skin.

Triamcinolone (Triderm 0.1%, Aristocort 0.025%, 0.1%, and 0.5% cream)

Treats inflammatory dermatitis that is responsive to steroids. Decreases inflammation by suppressing the migration of polymorphonuclear leukocytes and reversing capillary permeability.

Dosing

Adult

Apply thin film bid/tid until favorable response

Pediatric

Administer as in adults

Interactions

None reported

Contraindications

Documented hypersensitivity; fungal, viral, and bacterial skin infections

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Do not use in patients diagnosed with decreased skin circulation

Hydrocortisone (Cortaid 1%, Cortizone-10, Westcort 0.2%)

Treats inflammatory dermatitis responsive to steroids. Decreases inflammation by suppressing the migration of polymorphonuclear leukocytes and reversing capillary permeability.

Dosing

Adult

Apply thin film to affected area tid/qid until favorable response

Pediatric

Administer as in adults

Interactions

None reported

Contraindications

Documented hypersensitivity; viral, fungal, or tubercular skin infections

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Prolonged use, applying over large surface areas, application of potent steroids, and occlusive dressings may increase systemic absorption of corticosteroids and may cause Cushing syndrome, reversible HPA axis suppression, hyperglycemia, and glycosuria

Follow-up

Further Outpatient Care

Follow-up care is generally unnecessary for millipede envenomation unless local complications ensue or the eyes are involved.
In ocular cases, the patient should be examined daily until the eye is healed.

Deterrence/Prevention

Beyond avoidance of handling millipedes, little deterrence is required.

Complications

Cutaneous exposures generally heal without complications.
Conjunctivitis or corneal ulcerations can complicate eye exposures.

Prognosis

Millipede envenomations are self-limited.

Miscellaneous

Medicolegal Pitfalls

Failure to refer a patient suffering from eye exposure to an ophthalmologist for follow-up care could lead to a worse outcome.

Multimedia

Media file 1: The desert millipede, Orthoporus ornatus. Photo by Robert Norris, MD.

Media file 2: The desert millipede, Orthoporus ornatus. Photo by Robert Norris, MD.

Media file 3: Millipede contact injury on day 3 following exposure.

References

Dar NR, Raza N, Rehman SB. Millipede burn at an unusual site mimicking child abuse in an 8-year-old girl. Clin Pediatr (Phila). Jun 2008;47(5):490-2. [Medline].
Hare T. Poisonous Dwellers of the Desert. Tucson, AZ: Southwest Parks and Monuments Association; 1995.
Hendrickson RG. Millipede exposure. Clin Toxicol (Phila). 2005;43(3):211-2. [Medline].
Hudson BJ, Parsons GA. Giant millipede 'burns' and the eye. Trans R Soc Trop Med Hyg. Mar-Apr 1997;91(2):183-5. [Medline].
Mason GH, Thomson HD, Fergin P, Anderson R. Spot diagnosis. The burning millipede. Med J Aust. Jun 6 1994;160(11):718, 726. [Medline].
Peters S. A Colour Atlas of Arthropods in Clinical Medicine. Barcelona, Spain: Wolfe Publishing Ltd; 1992.
Radford AJ. Giant millipede burns in Papua New Guinea. P N G Med J. Sep 1976;18(3):138-41. [Medline].
Radford AJ. Millipede burns in man. Trop Geogr Med. Sep 1975;27(3):279-87. [Medline].
Williams LA, Singh PD, Caleb-Williams LS. Biology and biological action of the defensive secretion from a Jamaican millipede. Naturwissenschaften. 1997;84(4):143-4. [Medline].

Keywords

millipede envenomations, millipede sting, millipede bite, Diplopoda, Arthropoda, millipede exposure, centipede

Contributor Information and Disclosures

Author

Robert L Norris, MD, Associate Professor, Department of Surgery; Chief, Division of Emergency Medicine, Stanford University Medical Center
Robert L Norris, MD is a member of the following medical societies: American College of Emergency Physicians, American Medical Association, California Medical Association, International Society of Toxinology, Society for Academic Emergency Medicine, and Wilderness Medical Society
Disclosure: Nothing to disclose.

Medical Editor

James Li, MD, Former Assistant Professor, Division of Emergency Medicine, Harvard Medical School; Board of Directors, Remote Medicine
Disclosure: Nothing to disclose.

Pharmacy Editor

John T VanDeVoort, PharmD, Regional Director of Pharmacy, Sacred Heart & St. Joseph's Hospitals
John T VanDeVoort, PharmD is a member of the following medical societies: American Society of Health-System Pharmacists
Disclosure: Nothing to disclose.

Managing Editor

Richard H Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center
Richard H Sinert, DO is a member of the following medical societies: American College of Physicians and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Scott H Plantz, MD, FAAEM, Associate Clinical Professor of Emergency Medicine, Rosalind Franklin University of Medicine and Science, Chicago Medical School; Medical Director, WeCare Med, Inc
Scott H Plantz, MD, FAAEM is a member of the following medical societies: American Academy of Emergency Medicine
Disclosure: Nothing to disclose.

Further Reading