This medication is used to treat "cold sores/fever blisters" (herpes labialis). It can speed up healing of the sores and decrease symptoms (such as tingling, pain, burning, itching). Acyclovir belongs to a class of medications known as antivirals. It works by stopping the growth of the virus. This medication does not cure herpes, and it does not prevent passing the infection to someone else. It does not prevent a future occurrence.
OTHER USES: This section contains uses of this drug that are not listed in the approved US professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.
This medication may also be used to treat genital herpes. Other medications taken by mouth may be more effective for genital herpes. Discuss your treatment options with your doctor. This medication does not cure herpes or prevent infection of sexual partners.
Read the Patient Information Leaflet available from your pharmacist. Consult your doctor or pharmacist if you have any questions.
Use this medication at the first sign of infection (such as tingling, burning, redness). Wash your hands with soap and water before and after applying this medication. Clean and dry the affected areas before applying the medication. Apply to the affected area and rub in gently, usually 5 times a day (every 3 to 4 hours) for 4 days for cold sores, or as directed by your doctor. Apply enough cream to cover all affected areas (red/tingling/burning areas, sores).
Apply to skin only. Do not apply this medication in the eyes or nose, inside the mouth, or inside the vagina. If you do get medication in those areas, flush with plenty of water.
Dosage is based on your medical condition, type of infection, and response to treatment. Do not use this drug more often or for longer than prescribed.
Use this medication regularly to get the most benefit from it. This medication works best when the amount of drug absorbed by the skin stays at a constant level. Therefore, use this drug at evenly spaced intervals. To help you remember, use it at the same times each day.
To prevent washing off the medication, do not bathe, shower, or swim right after applying it.
If applying to genital herpes sores, use a finger cot or rubber gloves to avoid spreading the infection.
Do not apply other skin products (such as drugs, cosmetics, sun screens, or lip balms) unless told to do so by your doctor. Do not cover the area with plastic or waterproof bandages unless told to do so by your doctor.
Cold sores (herpes) can spread easily. Acyclovir cream does not prevent the spread of herpes. Avoid close physical contact with others (such as kissing) during an outbreak until the cold sores have completely healed. Also, try not to touch the cold sore, and wash your hands if you do touch the cold sore.
If you are using acyclovir for treatment of genital herpes, it is important to follow safe sex practices to reduce the risk of giving herpes to your partner, even if there are no symptoms present. Always use a condom made of latex or polyurethane. When you have symptoms or are experiencing an outbreak, do not have sexual contact with your partner.
Tell your doctor if your condition persists or worsens after treatment is finished.
Dry/cracked lips, burning, stinging, or flaky skin may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
In the US -
Before using acyclovir, tell your doctor or pharmacist if you are allergic to it; or to valacyclovir; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history.
Tell your doctor if you are pregnant before using this medication. Discuss the risks and benefits with your doctor.
Acyclovir may pass into breast milk in small amounts. However, the drug is unlikely to harm a nursing infant. Consult your doctor before breast-feeding. Avoid breastfeeding if you have herpes sores on or near your breast.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
This medicine may be harmful if swallowed. If swallowing or overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
Do not share this medication with others. Doing so may spread the infection.
Cold sore outbreaks can be caused by many factors such as stress, hormonal changes (such as pregnancy, menstrual period), injury/surgery on the mouth (such as dental work), tiredness, sunlight, cold weather, or fever/cold/flu.
If you have genital herpes sores, wear loose-fitting clothing to keep from irritating them.
If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature. Firmly screw the cap back on the tube of medication after each use. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised April 2014. Copyright(c) 2014 First Databank, Inc.
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