This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
Brand Names: US
Brand Names: Canada
APO-Acyclovir; TARO-Acyclovir; Zovirax
What is this drug used for?
- It is used to treat cold sores.
- It is used to treat genital warts.
- It is used to treat shingles or certain other herpes infections.
What do I need to tell my doctor BEFORE I take this drug?
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have a milk allergy.
This drug may interact with other drugs or health problems.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take this drug?
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
- This drug is not a cure for herpes infections. Talk with the doctor.
- If you have genital herpes, this drug will not stop it from spreading. Do not have any kind of sex when you have sores or other signs of genital herpes. Genital herpes can also be spread if you do not have any signs. Do not have any kind of sex without using a latex or polyurethane condom. Talk with your doctor.
All other products:
- This drug will not cure cold sores. If you have questions, talk with the doctor.
- Talk with your doctor before you use other drugs or products on your skin.
- Do not give this drug to younger children. The chance of choking may be raised.
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like 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.
What are some other side effects of this drug?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Skin irritation.
- Burning or stinging.
- Dry or cracked lips.
- Flakiness of the skin.
- Dry skin.
- Pain where it was placed.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
How is this drug best taken?
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Use as you have been told, even if your signs get better.
- Do not take this drug by mouth. Use on your skin only. Keep out of your mouth, nose, and eyes (may burn).
- Wash your hands before and after use.
- Clean affected part before use. Make sure to dry well.
- Put a thin layer on the affected skin and rub in gently.
- Use at the first sign of a cold sore.
- Avoid putting on healthy skin.
- Do not rub the cold sore. Rubbing the cold sore may make it worse. It may also cause the cold sore to spread to other areas around the mouth.
- Use a rubber glove to put on the ointment. This helps to prevent the spread of infection.
- Use within 1 hour after the first signs of a cold sore. Put on the same side of the mouth as the cold sore.
- Dry your hands and place the tablet in your mouth above the incisor tooth between the upper cheek and gum. Leave the tablet in place until it dissolves.
- Do not swallow whole. Do not chew, break, or crush.
- Do not suck on this product.
- Do not remove the tablet from the tablet pack until you are ready to put in this drug. Put in the tablet right away after opening the blister pack. Do not store the removed tablet for future use.
- You may eat and drink when using this drug. Avoid doing things that may knock the tablet loose like chewing gum, touching the tablet, wearing upper dentures, and brushing your teeth.
- If your mouth gets dry when using this drug, drink more liquids.
- If the drug does not stick or falls out within the first 6 hours, put the same tablet back in. If you cannot do this, put in a new tablet.
- If the drug is swallowed within the first 6 hours, drink a glass of water and put in a new tablet.
- If the drug falls out or is swallowed after the first 6 hours, you do not need to re-apply a tablet.
What do I do if I miss a dose?
- Put on a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not put on 2 doses at the same time or extra doses.
How do I store and/or throw out this drug?
- Store at room temperature. Do not freeze.
- Protect from heat.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
- Store in a dry place. Do not store in a bathroom.
General drug facts
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
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