Coral Snake Envenomation Medication

Definitive therapy for coral snake envenomation is antivenom administration. Antivenom (usually derived from horses or sheep) is generally specific for closely related species of snakes, and no advantage exists to giving antivenom developed for unrelated snakes. Administering antivenom made from the venoms of unrelated snakes may add complications of acute allergic reaction (eg, anaphylactoid reactions, delayed serum sickness) to an already serious situation. If specific antivenom is unavailable, compression and immobilization should be maintained and the airway and respiratory status supported as necessary. An appropriately applied compression/immobilization device should be removed only after supportive measures are in place and antivenom is obtained (if available).

In the United States, the product used to treat Micrurus bites for the last several decades, Wyeth's Micrurus fulvius Antivenin, is no longer in production. Other antivenoms are produced in other countries (eg, Brazil, Costa Rica) for non-North American coral snakes. Mexico produces an antivenom that is likely effective for coral snake bites in the United States. It may prove that one of these exotic antivenoms will be required to be imported into the United States for use in serious bites here. In the absence of such an antivenom, care must be entirely supportive.

Care for persons bitten by Sonoran coral snakes is entirely supportive because no specific antivenom is available for this species.

Any appropriate, available antivenom should be administered according to the manufacturer's instructions.

As with any form of bite, tetanus status should be updated as necessary.

Antibiotic prophylaxis is not indicated. Because of the relative paucity of enzymatic necrotic components in their venoms, coral snake bites tend to cause little local tissue damage, and secondary infections are rare.

Class Summary

Imparts passive immunity to the patient against the venom components of the snake(s) for which it is manufactured. Heterologous antibodies administered bind with venom antigens and block their deleterious effects.

Antivenin, eastern & Texas coral snakes

Historically the DOC for significant bites by M fulvius (eastern coral snake) and M tener (Texas coral snake); however, it is no longer being produced. Unless another known effective antivenom is available, care for victims bitten by coral snakes in the United States will have to rely entirely on supportive care (as per the text above), though the outcome should still be good.

Class Summary

H1 and H2 blockers may blunt or prevent acute allergic reaction when given before the administration of antivenom. If an anaphylactoid reaction occurs despite pretreatment, further antihistamine dosing may be required. They are also useful in managing pruritus in cases of delayed serum sickness, which may appear days to weeks following antivenom treatment.

Diphenhydramine (Benadryl)

Administered parenterally and often is the H1 blocker of choice in treating or preventing anaphylactic/anaphylactoid reactions. Also effective in oral form for treating itching associated with serum sickness.

Cimetidine (Tagamet)

Administered parenterally and often is the H2 blocker of choice in treating or preventing anaphylactoid reactions. Use this medication in addition to H1 antihistamines.

Class Summary

These agents are useful in treating acute allergic reactions that may occur with antivenom administration and in supporting the blood pressure and tissue perfusion of hypotensive patients with shock unresponsive to IV fluids and antivenom.

Epinephrine (EpiPen, Adrenaline)

DOC for treating anaphylactoid reactions. Has alpha-agonist effects that increase peripheral vascular resistance and reverse peripheral vasodilatation, systemic hypotension, and vascular permeability. Conversely, beta-agonist activity of epinephrine produces bronchodilatation, chronotropic cardiac activity, and positive inotropic effects.

Dopamine (Intropin)

May be required to support BP with hypotension caused by anaphylactoid reaction that is unresponsive to fluids and epinephrine or by direct coral snake venom effects that are unresponsive to fluids and antivenom.

Norepinephrine (Levophed)

May be used as alternative to dopamine to support BP in the face of hypotension caused by anaphylactoid reaction unresponsive to fluids and epinephrine.

Class Summary

Essential for management of acute and delayed allergic phenomena following antivenom administration. Steroids have no primary role in the management of snake envenomation.

Methylprednisolone (Solu-Medrol, Adlone)

Ameliorates the delayed effects of anaphylactoid reactions and may prevent biphasic anaphylaxis. In severe cases of serum sickness, parenteral steroids may reduce the inflammatory effects of this immune-complex mediated disease.

Prednisone (Deltasone)

This or other PO forms of corticosteroids (eg, prednisolone) are useful in managing mild-to-moderate serum sickness on an outpatient basis.

Class Summary

Immune globulins bind toxoids, stimulate an immune response, and offer transient protection while the host immune system develops antibodies.

Tetanus immune globulin (TIG)

Used for passive immunization if wound might be contaminated with tetanus spores when the patient has no history of completing a primary tetanus immunization series.

Class Summary

Used to induce active immunity against tetanus.

Tetanus toxoid adsorbed or fluid

The immunizing agent of choice for most adults and children >7 y is tetanus and diphtheria toxoids. Necessary to administer booster doses to maintain tetanus immunity throughout life. Pregnant patients should receive only tetanus toxoid, not a diphtheria antigen-containing product. In children and adults, may administer into deltoid or midlateral thigh muscles. In infants, preferred site of administration is the mid-thigh laterally.