The drug known by its generic name, Acyclovir, belongs to the synthetic nucleoside analogues group of drugs used primarily to treat particular viral infections. Acyclovir is a prescriptive medication that prevents the division and multiplication of viruses responsible for said infections.

The Oldest Treatment for Herpes Simplex 1 and Simplex 2 So Far

Manufactured by GlaxoSmithKline and marketed as Zovirax, it comes in liquid, capsule and tablet forms. In the 1980s, the U.S. FDA (Food and Drug Administration) approved the drug for use against the virus known as varicella-zoster in the treatment of viral infections which caused shingles and chicken pox. Doctors have also prescribed acyclovir in the treatment of the Epstein-Barr virus which causes mononucleosis.

But acyclovir remains the oldest form of treatment for the herpes simplex 1 and simplex 2 viruses, or cold sores and genital herpes, which cause infections in those afflicted with HIV. Acyclovir is considered the first defense against viruses of the herpes simplex type. A study published last year, however, revealed that herpes strains which are resistant to acyclovir could develop over a certain period of time. This resistance can occur in individuals with healthy and weakened immune systems.

How Acyclovir Works

When a virus takes over a living cell and reproduces itself, at the host cell’s expense, acyclovir is converted into an activated form by the same virus, enabling it to use acyclovir’s active form instead of the nucleoside which it normally uses in the manufacture of DNA; DNA is a crucial element in the replication of a virus. When the active acyclovir is incorporated into a new virus in the DNA, production of DNA stops.

Simply put, cells which have been virally infected tend to absorb more of the acyclovir than their normal counterparts; therefore there is more conversion of it into active forms, a condition which helps prolong the anti-viral activity. In March of 1982, the USFDA approved the use of acyclovir. Aside from acyclovir’s availability in 200 mg capsules, 400mg and 800mg tablets, and 200mg and 5ml liquid suspension, it is also available as a 50mg or 40ml injection, a 500mg and 1000mg powder and as 5% ointment.

Knowing When to Take Acyclovir

Acyclovir is not a curative treatment for viral infections but it can shorten the duration of the infections and lessen their possibility of developing into more serious medical conditions. Taking acyclovir for treatment of genital herpes can help reduce its severity or prevent it from further recurrences.

Acyclovir helps in reducing the severity of either chicken pox or shingles. The latter is experienced as a painful rash which could develop several years after having had chicken pox with the reactivation of the virus.

How Acyclovir May be Taken

In initial cases of genital herpes, acyclovir helps reduce lesions and decreases severity and frequency of infections which are recurrent. For shingles, acyclovir helps reduce pain, shorten the duration for healing, and halts the formation of more lesions and further spread of the virus.

Fever is reduced if acyclovir is used with 24 hours after the onset of chicken pox. Acyclovir may be used intravenously for patients who have severe cases of genital herpes as well as those whose immune systems are compromised. Acyclovir ointment is also used as a topical treatment for initial cases of herpes.

Dosages for Daily or Episodic Therapy

Depending on the severity of the genital herpes infection of an individual who has it for the first time, an oral dosage of acyclovir at 400mg thrice a day has been recommended by the CDCP or Center for Disease Control and Prevention; this dosage has to be ingested between seven and ten days.

The patient may then choose to have daily or episodic therapy; the former is also known as suppressive therapy. Those who elected episodic therapy can choose to take acyclovir orally at 400mg thrice daily for a total of five days, 800mg thrice daily for a total of two days or 800mg twice a day for a total of five days.

Dosage for Those with Existing HIV Conditions

Patients who have existing conditions of HIV should take 400mg of oral acyclovir thrice a day between five and ten days. For suppressive therapy, the CDCP recommends 400mg of oral acyclovir twice daily; those who are already infected with HIV should take it between 400mg and 800mg two or three times daily.

Acyclovir is safe to be taken with or without prior ingestion of food. The intravenous dosage for adults is every eight hours at 5 to 10mg/kg for a week or seven days. Acyclovir is stored between 15° and 25°C or 59° and 77°F) or room temperature.

Side Effects and Cautionary Advice to Nursing Women

Like all medications, acyclovir has side effects, too. The more common ones include diarrhea, headache, vomiting, rash, and nausea. There have been reports of seizures, hepatitis, agitation, hypersensitivity reaction, muscle pain, and anemia, all of which must be reported to the patient’s doctor for advisement.

While there haven’t been sufficient clinical studies on the use of acyclovir by pregnant women and subsequent adverse effects, nursing women are cautioned against ingesting acyclovir since this can be transferred to an infant as an excretion in breast milk.