Famciclovir 250 mg, 500 mg Prescribed Online

Famciclovir is an antiviral medicine. It is used to treat or prevent infections caused by certain kinds of viruses. It treats shingles caused by herpes zoster. It also treats outbreaks of herpes simplex that cause cold sores around the mouth, sores around the anus and genital herpes.¹

It works by stopping the spread of the herpes virus in the body. However, famciclovir does not cure herpes infections and may not stop the spread of herpes virus to other people. The viruses that cause these infections continue to live in the body even between outbreaks. Famciclovir decreases the severity and length of these outbreaks. It helps the sores heal faster, keeps new sores from forming and decreases pain/itching. This medication may also help reduce how long pain remains after the sores heal.²

Famciclovir should be taken by mouth with or without food as directed by your doctor, usually two to three times a day. The dosage is based on your medical condition and response to treatment. It is most effective when started at the first sign of an outbreak, as directed by your doctor. It may not work as well if you delay treatment.³

Famciclovir works best when the amount of drug in your body is kept at a constant level. Take this drug at evenly spaced intervals.⁴ To help you remember, take it at the same times each day.

Continue to take this medication until the full prescribed amount is finished. Do not change your dose, skip any doses or stop this medication early without your doctor's approval.

Tell your doctor if your condition lasts or gets worse.

Continue to take famciclovir even if you feel well. Do not stop taking famciclovir without talking to your doctor.

When taken at the first sign of an outbreak, famciclovir symptoms usually improve within 48 hours. Cold sores usually take two to four weeks to completely heal.⁵

The viruses that cause shingles and herpes infections continue to live in the body even between outbreaks. Famciclovir decreases the severity and length of these outbreaks; and may decrease the symptoms of pain, burning, tingling, tenderness and itching; help sores heal; and prevent new sores from forming.⁶

When famciclovir is used to treat shingles, it is usually taken three times a day for seven days.

When used to treat cold sores and fever blisters, it is usually taken as one dose at the earliest sign or symptom of a cold sore.

When famciclovir is used to treat repeat outbreaks of genital herpes, it is usually taken twice a day for one day, starting within six hours of the first sign or symptom of the condition. To keep genital herpes from returning, famciclovir is usually taken twice a day for up to one year.

Take famciclovir exactly as directed.

Famciclovir is available by prescription⁷ and can be purchased online. Start an online consultation for viral infections, such as shingles and herpes, with RedBox Rx to see if famciclovir could be right for you. 

With RedBox Rx, famciclovir starts at just $40 per treatment (21 tablets), one of the lowest prices available online. No insurance required.

Before taking famciclovir:

• Tell your doctor and pharmacist if you are allergic to famciclovir, penciclovir cream (Denavir), acyclovir (Zovirax), any other medications or lactose.

• Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplement, and herbal products you are taking or plan to take, especially probenecid (Benemid).

• Tell your doctor if you have or have ever had problems with your immune system, human immunodeficiency virus infection (HIV) or acquired immunodeficiency syndrome (AIDS); galactose intolerance or glucose-galactose malabsorption (inherited conditions where the body is not able to tolerate lactose); or kidney or liver disease.

• Tell your doctor if you are pregnant, plan to become pregnant or are breastfeeding. If you become pregnant while taking famciclovir, call your doctor.

You should know that famciclovir may make you drowsy, dizzy, confused or disoriented. Do not drive a car or operate machinery until you know how this medication affects you.

Unless your doctor tells you otherwise, continue your normal diet.

Take the missed dose as soon as you remember it and take any remaining doses for that day at evenly spaced intervals. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Famciclovir may cause side effects, including:

• Headache.

• Nausea.

• Vomiting.

• Diarrhea or loose stools.

• Gas.

• Stomach pain.

• Tiredness.

• Rash.

• Itching.

• Painful menstrual periods.

Tell your doctor if any of these symptoms are severe or do not go away.

Famciclovir may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children, as many containers (such as weekly pill minders and those for eye drops, creams, patches and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and out of their sight and reach.

Unneeded medications should be disposed of in special ways to ensure that pets, children and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community.

In case of overdose, call the poison control helpline at 1-800-222-1222. If the victim has collapsed, had a seizure, has trouble breathing or can't be awakened, immediately call emergency services at 911.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your response to famciclovir.

Do not have sexual intercourse when you are having an outbreak of genital herpes. However, genital herpes can be spread to others, even when you do not have symptoms.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription. If you still have symptoms of infection after you finish the famciclovir, call your doctor.

It is important for you to keep a written list of all the prescription and nonprescription (over the counter) medicines you are taking, as well as any products such as vitamins, minerals or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

• Famvir^®

¹WebMD

²WebMD

³WebMD

⁴Cleveland Clinic

⁵Medzino

⁶WebMD

⁷Mayo Clinic

National Library of Medicine

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