The Walking Dead and Acyclovir

By Jomvie

People die and come back to life. Their bodies continue to decay but their instinct for food remains; they go out searching for scents of people or animals that are alive which pushes further their drive for satiety—the only remaining instinct. Sounds familiar? Should be. This is the concept of the popular comic book and TV series “The Walking Dead”.

This may sound fictional but do you know that Acyclovir, a medication used to treat and control cold sore (herpes labialis) can make you think you are one of the characters of the Walking Dead world? By the way, I’m talking about the zombies.

There is quite a link between The Walking Dead and acyclovir. This anti-viral drug has an adverse effect that leads to the patient becoming delusional and thinks that he or she is dead, has missing body parts, or his body is rotting and decaying. This mental disorder is called Cotard delusion.

About Acyclovir

800px-Aciclovir_substance_photoAcyclovir (aciclovir), which also goes by the brand names Cyclovir, Herpex, Zovirax, Zoral, and Imovir. It is one of the most commonly used antiviral drugs for the treatment of herpes simplex infections as well as varicella zoster (chicken pox) and herpes zoster (shingles).

It is considered to be a prodrug or a precursor drug in which it is administered in its inactive form and is transformed inside the body to its active form. It is manufactured and administered as tablets, topical creams, intravenous preparations, and ophthalmic solutions.

The cream forms are primarily used in the treatment of labial herpes simplex infections (cold sores). The intravenous injections are used when high concentrations of acyclovir are required in treating infections such as HSV encephalitis, acute retinal necrosis, and disseminated zoster disease.

Adverse Effects of Acyclovir

In approximately 1% of patients taking oral or intravenous acyclovir, there were reports of complaints of headache, nausea, vomiting, and diarrhea. In large doses, patients have experienced hallucinations. Infrequently, some patients (less than 1%) have experienced agitation, confusion, vertigo, and dizziness. Dermatological adverse effects like Steven-Johnson syndrome, toxic epidermal necrolysis, thrombotic thrombocytopenic purpura were also reported.

The kidneys may also be affected due to the crystallization of acyclovir leading to nephrotoxicity. Rapid infusion intravenously usually lead to this. Intravenous administration may also affect the brain causing encepalopathy.

Topical administration in about 1% of patients may also cause dry or flaking skin or transient stinging or burning sensations. Itching is also an infrequent adverse effect.

When applied to the eyes, acyclovir is also associated with transient mild stinging and in worse cases, superficial punctate keratitis and allergic reactions.

About 1% of patients taking acyclovir orally experience some psychiatric side effects. One of these mental disorders is Cotard delusion. The symptoms of Cotard delusion are associated with high serum concentration of 9-Carboxymethoxymethylguanine (CMMG), a compound which is the main metabolite of the acyclovir. Patients who suffered from psychiatric disorders after taking acyclovir therapy have concentrations of CMMG that are higher than normal.

About Cotard Delusion

Cotard delusion/syndrome (Walking Corpse Syndrome) is a rare mental disorder where people with this disease has a delusional belief that they are dead, either literally or figuratively. The central symptom of Cotard delusion is the delusion of negation. Patients who suffer from this psychiatric illness often deny that they exist or a certain part of their body exists.

The following are the three stages of Cotard syndrome:

  1. Germination – In this stage, the patient experiences psychotic depression and hypochondriasis (health phobia/anxiety). There is an overwhelming preoccupation towards  an inaccurate perception of the body having a severe illness without an actual medical condition.
  2. Blooming – This stage is characterized by the full-blown development of the syndrome and the delusion of negation.
  3. Chronic – This is characterized by severe delusions and chronic depression.

The delusions are comparable and are as strong as those of schizophrenic patients. Although the delusions are not yet characterized to be hallucinations, they are at the same level of perception.

Patients with Cotard delusion exhibit poor socialization and are typically withdrawn from others. They are also characterized to have poor hygiene and deficient in self-care abilities. So, imagine one of the zombies in a “The Walking Dead” episode and you can see the total picture. Nevertheless, this is a mental disorder and patients who suffer this kind of disease are considered victims.

The Link Between Zombies and Acyclovir Ends There

In contrast to the zombies from the comic or TV show, patients with Cotard delusion have a mind set that they are dead and sometimes have the thoughts of missing body parts. They may also exhibit loss of appetite or think there is no need for them to eat; thus most of them literally die of starvation.

Proper medical attention and care are definitely required for persons with Cotard delusion. Like any psychiatric patient, the main goal of medical management for sufferers of Cotard delusion is to regain the neurochemical imbalance of the brain, establishing the care mechanism, and maintenance of proper nutrition and hygiene.

Psychiatric treatment methods like electroconvulsive therapy and pharmacotherapy are used to manage this type of mental illness. In the treatment of Cotard delusion as a result of acyclovir medication, hemodialysis have been reported to cure the disorder in a span of a few hours. Luckily, psychiatric hospitalization is not required in this kind of situation.

As a conclusion, it is imperative to take extra precautions when taking acyclovir in the treatment of cold sore. Pregnant women and patients with kidney disease or disorders are advised to avoid taking this medication in treating a herpes simplex infection.

Last Updated: November 27, 2013


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