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Western Equine Encephalitis Medication

  • Author: Mohan Nandalur, MD; Chief Editor: Burke A Cunha, MD  more...
Updated: Feb 29, 2016

Medication Summary

The drugs currently used in cases of Western equine encephalitis (WEE) consist of agents capable of ameliorating neurologic complications. Antipyretics are used as needed. Additionally, suitable analgesics and amnestics are appropriate once the patient is intubated.

Antibiotics are of no value in this situation and may predispose the patients to superinfections. Once the physician determines that the patient does not have a bacterial infection, antibiotics are discontinued.

Initiate anticonvulsants either when a seizure has occurred or is probable, particularly in the pediatric population, in whom prevalence is high.

Corticosteroids are administered early and serve multiple functions. They decrease inflammation, decrease cerebral edema, and correct any adrenocortical insufficiency.


Anticonvulsant agents

Class Summary

These agents prevent seizure recurrence and terminate clinical and electrical seizure activity.

Phenytoin (Dilantin)


Phenytoin may act in the motor cortex, where it may inhibit the spread of seizure activity. The activity of brain stem centers responsible for the tonic phase of grand mal seizures may also be inhibited.

Individualize the dose. Administer a larger dose before retiring if the dose cannot be divided equally. The rate of infusion must not exceed 50 mg per minute to avoid hypotension and arrhythmia.

Diazepam (Valium)


Diazepam depresses all levels of the CNS (eg, limbic, reticular formation), possibly by increasing the activity of gamma-aminobutyric acid (GABA). Alternatively, lorazepam can be used when indicated.



Class Summary

These agents have anti-inflammatory properties and cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli.

Dexamethasone (Baycadron)


Dexamethasone decreases inflammation by suppressing the migration of polymorphonuclear leukocytes and reducing capillary permeability.

Methylprednisolone (Solu-Medrol, Medrol, Depo-Medrol)


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


Antiviral agents

Class Summary

These agents consist of acyclovir and valacyclovir and are often used as empiric treatments for possible herpes simplex encephalitis.

Acyclovir (Zovirax)


This is a herpes virus–specific antiviral used for peripheral and systemic manifestations of acute viral illness.



Class Summary

These agents are helpful in relieving the associated lethargy, malaise, and fever associated with the disease.

Acetaminophen (Acephen, FeverAll, Tylenol)


Acetaminophen inhibits the action of endogenous pyrogens on heat-regulating centers; it reduces fever by a direct action on the hypothalamic heat-regulating centers, which, in turn, increases the dissipation of body heat via sweating and vasodilation.

Contributor Information and Disclosures

Mohan Nandalur, MD Staff Physician, Department of Internal Medicine, Section of Cardiovascular Medicine, Washington Hospital Center

Mohan Nandalur, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Cardiology, American College of Physicians-American Society of Internal Medicine, Phi Beta Kappa

Disclosure: Nothing to disclose.


Andrew W Urban, MD Chief, Section of Infectious Diseases, Middleton Memorial Veterans Hospital; Clinical Assistant Professor, Department of Internal Medicine, University of Wisconsin at Madison School of Medicine and Public Health

Andrew W Urban, MD is a member of the following medical societies: American College of Physicians-American Society of Internal Medicine

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

John L Brusch, MD, FACP Assistant Professor of Medicine, Harvard Medical School; Consulting Staff, Department of Medicine and Infectious Disease Service, Cambridge Health Alliance

John L Brusch, MD, FACP is a member of the following medical societies: American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Chief Editor

Burke A Cunha, MD Professor of Medicine, State University of New York School of Medicine at Stony Brook; Chief, Infectious Disease Division, Winthrop-University Hospital

Burke A Cunha, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.


Kenneth C Earhart, MD Deputy Head, Disease Surveillance Program, United States Naval Medical Research Unit #3

Kenneth C Earhart, MD is a member of the following medical societies: American College of Physicians, American Society of Tropical Medicine and Hygiene, Infectious Diseases Society of America, and Undersea and Hyperbaric Medical Society

Disclosure: Nothing to disclose.

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