Acyclovir Oral Suspension

Name: Acyclovir Oral Suspension

Indications and Usage for Acyclovir Oral Suspension

Herpes Zoster Infections: Acyclovir is indicated for the acute treatment of herpes zoster (shingles).

Genital Herpes: Acyclovir is indicated for the treatment of initial episodes and the management of recurrent episodes of genital herpes.

Chickenpox: Acyclovir is indicated for the treatment of chickenpox (varicella). 

Contraindications

Acyclovir is contraindicated for patients who develop hypersensitivity to acyclovir or valacyclovir.

Precautions

Dosage adjustment is recommended when administering Acyclovir to patients with renal impairment (see DOSAGE AND ADMINISTRATION). Caution should also be exercised when administering Acyclovir to patients receiving potentially nephrotoxic agents since this may increase the risk of renal dysfunction and/or the risk of reversible central nervous system symptoms such as those that have been reported in patients treated with intravenous acyclovir. Adequate hydration should be maintained.

Information for Patients: 

Patients are instructed to consult with their physician if they experience severe or troublesome adverse reactions, they become pregnant or intend to become pregnant, they intend to breastfeed while taking orally administered Acyclovir, or they have any other questions.

Patients should be advised to maintain adequate hydration.

Herpes Zoster: There are no data on treatment initiated more than 72 hours after onset of the zoster rash. Patients should be advised to initiate treatment as soon as possible after a diagnosis of herpes zoster.

Genital Herpes Infections: Patients should be informed that Acyclovir is not a cure for genital herpes. There are no data evaluating whether Acyclovir will prevent transmission of infection to others. Because genital herpes is a sexually transmitted disease, patients should avoid contact with lesions or intercourse when lesions and/or symptoms are present to avoid infecting partners. Genital herpes can also be transmitted in the absence of symptoms through asymptomatic viral shedding. If medical management of a genital herpes recurrence is indicated, patients should be advised to initiate therapy at the first sign or symptom of an episode.

Chickenpox: Chickenpox in otherwise healthy children is usually a self-limited disease of mild to moderate severity. Adolescents and adults tend to have more severe disease. Treatment was initiated within 24 hours of the typical chickenpox rash in the controlled studies, and there is no information regarding the effects of treatment begun later in the disease course.

Drug Interactions:

See CLINICAL PHARMACOLOGY: Pharmacokinetics.

Carcinogenesis, Mutagenesis, Impairment of Fertility: 

The data presented below include references to peak steady-state plasma acyclovir concentrations observed in humans treated with 800 mg given orally 5 times a day (dosing appropriate for treatment of herpes zoster) or 200 mg given orally 5 times a day (dosing appropriate for treatment of genital herpes). Plasma drug concentrations in animal studies are expressed as multiples of human exposure to acyclovir at the higher and lower dosing schedules (see CLINICAL PHARMACOLOGY: Pharmacokinetics).

Acyclovir was tested in lifetime bioassays in rats and mice at single daily doses of up to 450 mg/kg administered by gavage. There was no statistically significant difference in the incidence of tumors between treated and control animals, nor did acyclovir shorten the latency of tumors. Maximum plasma concentrations were 3 to 6 times human levels in the mouse bioassay and 1 to 2 times human levels in the rat bioassay.

Acyclovir was tested in 16 in vitro and in vivo genetic toxicity assays. Acyclovir was positive in 5 of the assays.

Acyclovir did not impair fertility or reproduction in mice (450 mg/kg/day, p.o.) or in rats (25 mg/kg/day, s.c.). In the mouse study, plasma levels were 9 to 18 times human levels, while in the rat study, they were 8 to 15 times human levels. At higher doses (50 mg/kg/day, s.c.) in rats and rabbits (11 to 22 and 16 to 31 times human levels, respectively) implantation efficacy, but not litter size, was decreased. In a rat peri- and post-natal study at 50 mg/kg/day, s.c., there was a statistically significant decrease in group mean numbers of corpora lutea, total implantation sites, and live fetuses.

No testicular abnormalities were seen in dogs given 50 mg/kg/day, IV for 1 month (21 to 41 times human levels) or in dogs given 60 mg/kg/day orally for 1 year (6 to 12 times human levels). Testicular atrophy and aspermatogenesis were observed in rats and dogs at higher dose levels.

Pregnancy:

Teratogenic Effects:

Pregnancy Category B. Acyclovir administered during organogenesis was not teratogenic in the mouse (450 mg/kg/day, p.o.), rabbit (50 mg/kg/day, s.c. and IV), or rat (50 mg/kg/day, s.c.). These exposures resulted in plasma levels 9 and 18, 16 and 106, and 11 and 22 times, respectively, human levels. 

There are no adequate and well-controlled studies in pregnant women. A prospective epidemiologic registry of acyclovir use during pregnancy was established in 1984 and completed in April 1999. There were 749 pregnancies followed in women exposed to systemic acyclovir during the first trimester of pregnancy resulting in 756 outcomes. The occurrence rate of birth defects approximates that found in the general population. However, the small size of the registry is insufficient to evaluate the risk for less common defects or to permit reliable or definitive conclusions regarding the safety of acyclovir in pregnant women and their developing fetuses. Acyclovir should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Nursing Mothers:

Acyclovir concentrations have been documented in breast milk in 2 women following oral administration of Acyclovir and ranged from 0.6 to 4.1 times corresponding plasma levels. These concentrations would potentially expose the nursing infant to a dose of acyclovir up to 0.3 mg/kg/day. Acyclovir should be administered to a nursing mother with caution and only when indicated.

Pediatric Use:

Safety and effectiveness of oral formulations of acyclovir in pediatric patients younger than 2 years of age have not been established.

Geriatric Use:

Of 376 subjects who received Acyclovir in a clinical study of herpes zoster treatment in immunocompetent subjects ≥50 years of age, 244 were 65 and over while 111 were 75 and over. No overall differences in effectiveness for time to cessation of new lesion formation or time to healing were reported between geriatric subjects and younger adult subjects. The duration of pain after healing was longer in patients 65 and over. Nausea, vomiting, and dizziness were reported more frequently in elderly subjects. Elderly patients are more likely to have reduced renal function and require dose reduction. Elderly patients are also more likely to have renal or CNS adverse events. With respect to CNS adverse events observed during clinical practice, somnolence, hallucinations, confusion, and coma were reported more frequently in elderly patients (see CLINICAL PHARMACOLOGY, ADVERSE REACTIONS: Observed During Clinical Practice, and DOSAGE AND ADMINISTRATION).

How is Acyclovir Oral Suspension Supplied

Acyclovir Suspension (off-white, banana-flavored) containing 200 mg acyclovir in each teaspoonful (5 mL).

Bottle of 1 pint (473 mL) (NDC 40085-842-96).

Store at 15° to 25°C (59° to 77°F).

Manufactured for:
Renaissance Pharma, Inc.
Newtown, PA 18940
by
Glaxosmithkline
Mississauga, ON, CANADA

March 2014

Acyclovir Side Effects

More Common Side Effects

Some of the more common side effects of acyclovir include:

  • nausea

  • vomiting

  • diarrhea

  • headache

  • weakness

Serious Side Effects

Call your doctor right away if you have serious side effects. Call 9-1-1 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

  • Unusual changes in your mood or behavior. Symptoms can include:

    • aggressive behavior
    • unsteady or shaky movements
    • confusion
    • trouble speaking
    • hallucinations (seeing or hearing something that isn’t there)
    • seizures
    • coma (being unconscious for a long time)
  • Decrease in your red blood cells and platelets. Symptoms can include:

    • fatigue
  • Liver problems

  • Muscle pain

  • Skin reactions. Symptoms can include:

    • hair loss
    • rash
    • breaking or loosening of skin
    • hives
    • Stevens-Johnson syndrome. This is a rare, allergic skin reaction.
  • Changes in your vision

  • Kidney failure. Symptoms can include:

    • kidney or flank pain (pain in your side and back)
    • blood in your urine
  • Allergic reaction. Symptoms can include:

    • trouble breathing
    • swelling of your throat or tongue
    • rash
    • hives
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.

Acyclovir May Interact with Other Medications

An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well. To help prevent interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking.

To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking. Drug warnings

People with kidney problems

If you have kidney problems or a history of kidney disease, you may not be able to clear this drug from your body well. This may increase the levels of this drug in your body and cause more side effects.

This medication may also decrease your kidney function. This means your kidney disease may get worse.

Your doctor will adjust your dose depending on how well your kidneys are working.

Pregnant women

Acyclovir is a category B pregnancy drug. That means two things:

  1. Studies of the drug in pregnant animals have not shown a risk to the fetus.
  2. There aren’t enough studies done in pregnant women to show if the drug poses a risk to the fetus.

Talk to your doctor if you’re pregnant or planning to become pregnant. This drug should be used only if the potential benefit justifies the potential risk to the fetus.

Women who are breast-feeding

Acyclovir may pass into breast milk and may cause side effects in a child who is breastfed.

Talk to your doctor if you breastfeed your baby. You may need to decide whether to stop breastfeeding or stop taking this medication.

For seniors

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, more of a drug stays in your body for a longer time. This raises your risk of side effects.

For children

This drug hasn’t been studied in children younger than 2 years.

When to call the doctor

Call your doctor right away if you become pregnant while taking this drug.

Allergies

Acyclovir can cause a severe allergic reaction. Symptoms can include:

  • trouble breathing
  • swelling of your throat or tongue
  • rash
  • hives 

Call 9-1-1 or go to the nearest emergency room if you develop these symptoms.

Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).

(web3)