Acyclovir
From PharmDatabase.org
Generic name: Acyclovir
Brand names: Zovirax
Related Medical Conditions: Herpes
Related Groups: Antiviral
Contents |
What is Acyclovir?
Acyclovir is an antiviral drug. It slows the growth and spread of the herpes virus so that the body can fight off the infection. Acyclovir will not cure herpes, but it can lessen the symptoms of the infections.
Acyclovir is used to decrease pain and speed the healing of sores or blisters in people who have varicella (chickenpox), herpes zoster (shingles; a rash that can occur in people who have had chickenpox in the past), and first-time or repeat outbreaks of genital herpes (a herpes virus infection that causes sores to form around the genitals and rectum from time to time). Acyclovir is also sometimes used to prevent outbreaks of genital herpes in people who are infected with the virus.
Acyclovir Usage and Dosage
Treatment with acyclovir should be started as soon as possible after the first appearance of symptoms (such as tingling, burning, blisters).
Acyclovir comes as a tablet, a capsule, a suspension (liquid) to take by mouth? a cream and an ointment. It is usually taken with or without food two to five times a day for 5 to 10 days, starting as soon as possible after your symptoms begin. When acyclovir is used to prevent outbreaks of genital herpes, it is usually taken two to five times a day for up to 12 months. Take acyclovir at around the same times every day.
Take each dose with a full glass of water. Drink plenty of water while you are taking acyclovir to keep your kidneys working properly.
Acyclovir can be taken with or without food. Taking acyclovir with food may decrease stomach upset.
Shake the oral suspension (liquid) well just before you measure a dose. To be sure you get the correct dose, measure the liquid with a marked measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one. The dose of acyclovir will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of acyclovir. Your dose may be different if you have kidney disease. If your dose is different, do not change it unless your doctor tells you to do so.
The number of capsules or tablets or teaspoonfuls of suspension that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are taking acyclovir.
For oral dosage forms (capsules, oral suspension, or tablets):
- For treatment of genital herpes:
- Adults and children 12 years of age and older—200 milligrams (mg) five times a day for ten days.
- Children up to 12 years of age—Use and dose must be determined by the doctor.
- For prevention of recurrent outbreaks of genital herpes infections:
- Adults and children 12 years of age and older—200 to 400 mg two to five times a day for five days or up to twelve months, depending on how often your outbreaks of infection occur.
- Children up to 12 years of age—Use and dose must be determined by the doctor.
- For treatment of chickenpox:
- Adults and children who weigh over 88 pounds (40 kilograms)—800 mg four times a day for five days.
- Children 2 years of age and older and weighing 88 pounds (40 kilograms) or less—Dose is based on body weight and must be determined by the doctor. The usual dose is 20 mg per kilogram (kg) of body weight, up to 800 mg, four times a day for five days.
- Children up to 2 years of age—Use and dose must be determined by the doctor.
- For treatment of shingles:
- Adults and children 12 years of age and older—800 mg five times a day for seven to ten days.
- Children up to 12 years of age—Use and dose must be determined by the doctor.
For injection dosage form:
- For treatment of herpes of the brain, genitals, or mucous membranes, or for the treatment of shingles:
- Adults and children 12 years of age and older—Dose is based on body weight and must be determined by the doctor. The usual dose is 5 to 10 mg of acyclovir per kg (2.3 to 4.5 mg per pound) of body weight, injected slowly into a vein over at least a one-hour period, and repeated every eight hours for five to ten days.
- Children up to 12 years of age—Dose is based on body weight and must be determined by the doctor. The usual dose is 10 mg to 20 mg of acyclovir per kg (4.5 mg to 9.1 mg per pound) of body weight, injected slowly into a vein over at least a one-hour period and repeated every eight hours for seven to ten days.
- For treatment of widespread herpes virus infection in newborns:
- Infants from birth to 3 months of age—Dose is based on body weight and must be determined by the doctor. The usual dose is 10 mg of acyclovir per kg (4.5 mg per pound) of body weight, injected slowly into a vein over at least a one-hour period and repeated every eight hours for ten days.
The dose of topical acyclovir will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average dose of topical acyclovir. If your dose is different, do not change it unless your doctor tells you to do so.
For topical dosage form (cream): For herpes simplex infection:
- Adults—Apply to the affected area(s), four to six times a day, for up to ten days.
- Children—Use and dose must be determined by your doctor.
For topical dosage form (ointment): For herpes simplex infection:
- In the U.S.
- Adults—Apply to the affected area(s), every three hours, for a total of six times a day, for seven days.
- Children—Use and dose must be determined by your doctor.
- In Canada
- Adults—Apply to the affected area(s), four to six times a day, for up to ten days.
- Children—Use and dose must be determined by your doctor.
Acyclovir Side Effects
Acyclovir (tablet, capsule, suspension) may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- upset stomach
- vomiting
- diarrhea
- dizziness
- tiredness
- agitation
- pain, especially in the joints
- hair loss
- changes in vision
Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:
- hives
- rash or blisters
- itching
- difficulty breathing or swallowing
- swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
- hoarseness
- fast heartbeat
- weakness
- pale skin
- difficulty sleeping
- fever, sore throat, chills, cough, and other signs of infection
- unusual bruising or bleeding
- blood in the urine
- stomach pain or cramps
- bloody diarrhea
- decreased urination
- headache
- hallucinations (seeing things or hearing voices that do not exist)
- confusion
- aggressive behavior
- difficulty speaking
- numbness, burning, or tingling in the arms or legs
- temporary inability to move parts of your body
- shaking of a part of your body that you cannot control
- seizures
- loss of consciousness
Acyclovir (cream, ointment) may cause side effects:
- More common
- Mild pain, burning, or stinging
- Less common
- Itching
- Rare
- Itching, stinging, or redness of the genital area; skin rash
Other Drugs Interaction
Before taking acyclovir, tell your doctor if you are also taking probenecid (Benemid). If you are using probenecid, you may not be able to use acyclovir, or you may need dosage adjustments or special tests during treatment.
Acyclovir Storage
Store acyclovir at room temperature away from moisture and heat. Store away from heat and direct light. Keep the medicine from freezing.
