Zovirax 5% Cream 5gm
It is used to treat cold sores.
Drug Class
Antiviral
Pharmacologic Class
Synthetic nucleoside analog; DNA polymerase inhibitor
Pregnancy Category
Category B
FDA Approved
Dec 1997
DEA Schedule
Not Controlled
Overview
What is this medicine?
Acyclovir cream is an antiviral medicine used to treat cold sores (herpes labialis) on the face and lips. It works by stopping the cold sore virus from growing and spreading, which helps the sores heal faster and reduces pain and itching.
How to Use This Medicine
Proper Use of This Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Continue using the medication as directed, even if your symptoms improve.
Application Instructions
Apply this medication only to your skin, avoiding ingestion. Keep it away from your mouth, nose, and eyes, as it may cause irritation or burning.
Wash your hands before and after applying the medication.
Clean the affected area before application and ensure it is dry.
Gently rub a thin layer of the medication onto the affected skin.
Apply the medication at the first sign of a cold sore.
Avoid applying the medication to healthy skin, and refrain from rubbing the cold sore, as this may worsen the condition or cause it to spread to other areas around the mouth.
Storage and Disposal
Store the medication at room temperature, avoiding freezing temperatures.
Protect the medication from heat sources.
Keep all medications in a safe location, out of the reach of children and pets.
Missed Dose Instructions
If you miss a dose, apply it as soon as you remember.
If the missed dose is close to the time for your next scheduled dose, skip the missed dose and resume your regular application schedule.
Do not apply two doses at the same time or use extra doses to make up for a missed dose.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Continue using the medication as directed, even if your symptoms improve.
Application Instructions
Apply this medication only to your skin, avoiding ingestion. Keep it away from your mouth, nose, and eyes, as it may cause irritation or burning.
Wash your hands before and after applying the medication.
Clean the affected area before application and ensure it is dry.
Gently rub a thin layer of the medication onto the affected skin.
Apply the medication at the first sign of a cold sore.
Avoid applying the medication to healthy skin, and refrain from rubbing the cold sore, as this may worsen the condition or cause it to spread to other areas around the mouth.
Storage and Disposal
Store the medication at room temperature, avoiding freezing temperatures.
Protect the medication from heat sources.
Keep all medications in a safe location, out of the reach of children and pets.
Missed Dose Instructions
If you miss a dose, apply it as soon as you remember.
If the missed dose is close to the time for your next scheduled dose, skip the missed dose and resume your regular application schedule.
Do not apply two doses at the same time or use extra doses to make up for a missed dose.
Lifestyle & Tips
- Apply the cream at the first sign of a cold sore (tingling, itching, or redness).
- Wash your hands thoroughly before and after applying the cream.
- Apply only enough cream to cover the affected area, including the outer edge of the cold sore.
- Do not apply to eyes, inside the mouth, or inside the nose.
- Avoid touching the cold sore unnecessarily to prevent spreading the virus.
- Do not share the cream or personal items (e.g., towels, utensils) with others to prevent spreading the virus.
- Avoid activities that may irritate the cold sore (e.g., acidic foods, excessive sun exposure).
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Apply to affected area 5 times a day for 4 days
Condition-Specific Dosing:
herpesLabialis:
Apply to affected area 5 times a day for 4 days, starting at the first sign or symptom of recurrence.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Apply to affected area 5 times a day for 4 days (for children 12 years and older with herpes labialis). For younger children, consult physician.
Adolescent:
Apply to affected area 5 times a day for 4 days.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed (minimal systemic absorption)
Moderate:
No adjustment needed (minimal systemic absorption)
Severe:
No adjustment needed (minimal systemic absorption)
Dialysis:
No specific considerations for topical application due to minimal systemic absorption.
Hepatic Impairment:
Mild:
No adjustment needed (minimal systemic absorption)
Moderate:
No adjustment needed (minimal systemic absorption)
Severe:
No adjustment needed (minimal systemic absorption)
Pharmacology
Mechanism of Action
Acyclovir is a synthetic purine nucleoside analog with in vitro and in vivo inhibitory activity against herpes simplex virus (HSV) types 1 and 2. Acyclovir is phosphorylated to acyclovir monophosphate by virus-specific thymidine kinase (TK), then further converted to acyclovir triphosphate by cellular enzymes. Acyclovir triphosphate inhibits viral DNA replication by competing with deoxyguanosine triphosphate for incorporation into viral DNA, leading to chain termination and irreversible inactivation of viral DNA polymerase.
Pharmacokinetics
Absorption:
Bioavailability:
Negligible systemic absorption (plasma concentrations generally below detectable limits)
Tmax:
Not applicable (for systemic absorption)
FoodEffect:
Not applicable (topical administration)
Distribution:
Vd:
Not clinically relevant (minimal systemic absorption)
ProteinBinding:
Not clinically relevant (minimal systemic absorption)
CnssPenetration:
Limited (minimal systemic absorption)
Elimination:
HalfLife:
Not clinically relevant (minimal systemic absorption)
Clearance:
Not clinically relevant (minimal systemic absorption)
ExcretionRoute:
Not clinically relevant (minimal systemic absorption)
Unchanged:
Not clinically relevant (minimal systemic absorption)
Pharmacodynamics
OnsetOfAction:
Reduction in healing time and duration of pain/itching typically observed within 1-2 days of initiation.
PeakEffect:
Not precisely quantifiable for topical effect, but clinical benefit seen over the 4-day treatment course.
DurationOfAction:
Effect persists throughout the 4-day treatment course and contributes to faster lesion resolution.
Confidence:
Medium
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
If you experience any of the following symptoms, call your doctor immediately or seek emergency medical attention, as they may be signs of a severe and potentially life-threatening reaction:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Other Possible Side Effects
While many people taking this medication may not experience any side effects or only minor ones, it's essential to be aware of the following:
- Skin irritation
- Burning or stinging sensations
- Itching
- Dry or cracked lips
- Flakiness of the skin
- Dry skin
- Peeling
If any of these side effects or any others bother you or do not go away, contact your doctor for advice. Not all possible side effects are listed here. If you have questions or concerns about side effects, don't hesitate to reach out to your doctor.
Reporting Side Effects
To report side effects, you can contact the FDA at 1-800-332-1088 or visit their website at https://www.fda.gov/medwatch. Your doctor is also a valuable resource for medical advice about side effects.
If you experience any of the following symptoms, call your doctor immediately or seek emergency medical attention, as they may be signs of a severe and potentially life-threatening reaction:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Other Possible Side Effects
While many people taking this medication may not experience any side effects or only minor ones, it's essential to be aware of the following:
- Skin irritation
- Burning or stinging sensations
- Itching
- Dry or cracked lips
- Flakiness of the skin
- Dry skin
- Peeling
If any of these side effects or any others bother you or do not go away, contact your doctor for advice. Not all possible side effects are listed here. If you have questions or concerns about side effects, don't hesitate to reach out to your doctor.
Reporting Side Effects
To report side effects, you can contact the FDA at 1-800-332-1088 or visit their website at https://www.fda.gov/medwatch. Your doctor is also a valuable resource for medical advice about side effects.
Seek Immediate Medical Attention If You Experience:
- Severe burning, stinging, or itching after application
- Rash or hives
- Swelling of the face, lips, or tongue
- Difficulty breathing or swallowing (rare, but seek immediate medical attention)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins.
* Any existing health problems, as this medication may interact with other drugs or health conditions.
To ensure your safety, it is crucial to verify that this medication can be taken with all your current medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins.
* Any existing health problems, as this medication may interact with other drugs or health conditions.
To ensure your safety, it is crucial to verify that this medication can be taken with all your current medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Please note that this drug is not a cure for cold sores. If you have any questions or concerns, be sure to discuss them with your doctor.
Before using any other medications or products on your skin, including soaps, consult with your doctor to ensure safe use. Additionally, if you are pregnant, planning to become pregnant, or are breast-feeding, notify your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby.
Before using any other medications or products on your skin, including soaps, consult with your doctor to ensure safe use. Additionally, if you are pregnant, planning to become pregnant, or are breast-feeding, notify your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Topical overdose is unlikely due to minimal systemic absorption. Ingestion of the cream may cause mild gastrointestinal upset.
What to Do:
If ingested, drink water. For significant ingestion or unusual symptoms, contact a poison control center (Call 1-800-222-1222) or seek medical attention.
Drug Interactions
Monitoring
Routine Monitoring
Clinical assessment of lesion healing
Frequency: Daily during treatment
Target: Reduction in lesion size, crusting, and resolution of symptoms
Action Threshold: Lack of improvement or worsening of symptoms after 4 days; consider alternative diagnosis or treatment.
Symptom Monitoring
- Pain
- Itching
- Tingling
- Blister formation
- Crusting
- Redness
Special Patient Groups
Pregnancy
Acyclovir is Pregnancy Category B. Studies in animals have not shown harm to the fetus, and human data suggest low risk. Topical absorption is minimal, making it generally considered safe for use during pregnancy for cold sores.
Trimester-Specific Risks:
First Trimester:
Low risk due to minimal systemic absorption.
Second Trimester:
Low risk due to minimal systemic absorption.
Third Trimester:
Low risk due to minimal systemic absorption.
Lactation
Acyclovir is excreted in breast milk after systemic administration, but topical absorption is minimal. The amount transferred to breast milk is expected to be negligible, posing very low risk to the nursing infant. Compatible with breastfeeding.
Infant Risk:
Very low risk (L2)
Pediatric Use
Safe for use in children 12 years of age and older for herpes labialis. For younger children, use should be under the guidance of a healthcare professional.
Geriatric Use
No specific dose adjustments or precautions are necessary for elderly patients due to minimal systemic absorption.
Clinical Information
Clinical Pearls
- Early application (at the first sign of tingling, itching, or redness) is crucial for optimal efficacy.
- Acyclovir cream is for external use only and should not be used on mucous membranes (e.g., inside the mouth or nose, genitals, eyes).
- It does not prevent future outbreaks or transmission of the virus.
- Complete the full 4-day course of treatment even if the cold sore appears to be healing.
Alternative Therapies
- Penciclovir cream (Denavir)
- Docosanol cream (Abreva, OTC)
- Oral antivirals (e.g., acyclovir, valacyclovir, famciclovir) for more severe or frequent outbreaks.
Cost & Coverage
Average Cost:
Varies widely, typically $50-$150 per 5gm tube
Generic Available:
Yes
Insurance Coverage:
Tier 2 or 3 (generic often Tier 1)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.