Famvir for Shingles (Famciclovir)
Complete patient guide for uses, dosage, side effects, and safety information
Prescription RequiredQuick Facts
What Is Famvir for Shingles Used For?
Famvir is an antiviral medicine specifically designed to treat shingles in adults and adolescents. It helps manage the painful symptoms caused by the varicella zoster virus.
Primary Uses
Famvir treats shingles, a condition caused by the herpes virus called varicella zoster – the same virus that causes chicken pox. This virus can reactivate in your body even after many years, resulting in shingles with symptoms like a painful rash, burning sensation, and blisters.
How It Works
While Famvir doesn’t cure the viral infection, it helps relieve symptoms and shortens how long they last. The medicine works best when started as soon as possible after the first symptoms appear – ideally within 72 hours of the rash appearing.
Good to know: Famvir is not addictive and is only available with a doctor’s prescription.
How to Take Famvir for Shingles
Take Famvir tablets exactly as prescribed by your doctor. Swallow the tablets whole with a full glass of water, and they can be taken with or without food.
Dosage Instructions
The usual dose is one 250 mg tablet three times each day for seven days, beginning no later than 72 hours after the rash appears. Take one tablet in the morning, one in the afternoon, and one before bed. Try to take them at about the same time each day. Your doctor may prescribe a different dose based on your immune system function or kidney health.
What If You Miss a Dose?
Take the missed dose as soon as you remember, then take your next tablet at the usual time and continue normally. Don’t take two doses within one hour of each other – if this happens, skip the missed dose instead.
Important: Never take a double dose to make up for a missed one, as this may increase your chance of side effects.
Available Tablet Strengths
Side Effects
Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.
Common Side Effects
These side effects occur relatively frequently and usually don’t require emergency care:
- headache
- dizziness
- nausea or vomiting
- abdominal pain
- diarrhea
- itching or itchy rash
- abnormal liver function test results
Seek immediate medical attention if you experience:
- rash separate from shingles rash
- extreme sleepiness or confusion (especially in older people)
- hallucinations
- painful or swollen joints
- muscle aching, tenderness or weakness not from exercise
- yellowing of skin or eyes (jaundice)
- heart palpitations
- swelling below skin surface (face, eyes, throat)
- unexplained bruising or bleeding
- severe skin blistering
- purple patches or burning skin
- seizures or fits
- difficulty breathing, wheezing, or severe allergic reactions
Important Warnings
Before taking Famvir, it’s crucial to discuss your medical history and current health conditions with your doctor to ensure safe use.
Who Should Not Take Famvir for Shingles
Don’t take Famvir if you’re allergic to famciclovir, penciclovir (a related antiviral), or any other ingredients in the tablets. Signs of allergic reaction include shortness of breath, wheezing, swelling of face/lips/tongue, or skin rash and itching. Also avoid if the packaging is damaged or past its expiry date.
Medical Conditions to Discuss
Tell your doctor if you have problems with your immune system, kidneys, or liver, as your doctor may need to take extra precautions or adjust your dose. Also mention if you’re lactose intolerant, as the 250 mg tablets contain lactose.
Pregnancy and Breastfeeding
Famvir should not be used during pregnancy unless necessary. Your doctor will discuss the potential risks if you’re pregnant, planning to become pregnant, or breastfeeding, and will advise based on your personal situation’s benefits and risks.
Drug Interactions
Some medications may interfere with Famvir, so it’s important to tell your doctor about all medicines you’re taking, including over-the-counter products.
- probenecid (used to treat gout and increase penicillin levels)
- raloxifene (used to treat osteoporosis)
- medicines that can affect your kidneys
Alcohol & Driving
Famvir can affect your ability to drive or operate machinery safely, so take precautions until you know how the medication affects you.
Alcohol
The source material doesn’t specifically mention alcohol interactions with Famvir.
Driving and Operating Machinery
Be careful when driving, operating machinery, or doing jobs that require alertness until you know how Famvir affects you. This medicine can cause dizziness, sleepiness, or confusion in some people.
Temperature Regulation
No specific temperature regulation warnings are mentioned in the source material.
Storage
Store Famvir in its original container in a dry place at room temperature. Don’t store it in the bathroom, near sinks, in cars, or on window sills, as heat and dampness can damage the medicine. Keep it in a locked cupboard at least 1.5 meters above ground, away from children’s reach.
Overdose Information
If you think you or someone else has taken too much Famvir, immediately call your doctor, the Poisons Information Centre (13 11 26), or go to your nearest hospital emergency department. Show them the tablet pack, even if there are no symptoms. Taking too much Famvir may affect your kidneys and, in people with existing kidney problems, may rarely lead to kidney failure if the dose isn’t properly adjusted.
Frequently Asked Questions
Famvir works best when started as soon as possible after symptoms begin, ideally within 72 hours of the rash appearing. While it doesn’t cure the infection, it helps relieve symptoms and shortens their duration.
Yes, Famvir tablets can be taken with or without food. Swallow them whole with a full glass of water – there’s no need to chew or crush the tablets.
No, Famvir is not addictive. It’s an antiviral medication that’s only available with a doctor’s prescription.
Don’t stop taking Famvir or change the dosage without checking with your doctor first. If you stop suddenly, your condition may worsen or you may experience unwanted side effects. You must take the full course of treatment even if symptoms improve.
Take the missed dose as soon as you remember, then take your next tablet at the usual time. Don’t take two doses within one hour of each other – if this happens, skip the missed dose. Never take a double dose to make up for a missed one.
Yes, but elderly patients should be monitored carefully as they may be more prone to side effects like extreme sleepiness or confusion. Your doctor will determine the appropriate dose based on your individual health status.
The usual treatment course is seven days, taking one 250mg tablet three times daily. You must complete the full course even if your symptoms start improving after a few days to help clear up the infection properly.
Important Disclaimer
This information is intended for general educational purposes only and should not be considered medical advice. Always consult your healthcare provider or pharmacist before starting, stopping, or changing any medication.
If you think you may have a medical emergency, call your doctor or emergency services immediately.