Western Equine Encephalitis Medication
- Author: Mohan Nandalur, MD; Chief Editor: Burke A Cunha, MD more...
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.
Corticosteroids
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.
Antipyretics
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.
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