Famvir
Book a quick face-to-face video consultation with a certified prescribing pharmacist, nurse, or doctor. If approved, your Famvir will be prescribed* and delivered straight to your door with free next-day delivery†. No hidden fees. No delays. Just expert care.
* Includes Free Private Prescription & Consultation.
† Applies to UK only.
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MEDICAL INFORMATION
Famvir Key Facts
Other Related Names or Treatments
Valtrex
About Famvir
Famvir contains famciclovir as the active ingredient. It is classed as an antiviral drug and is used for the treatment of cold sores (herpes labialis, HSV-1)) and genital herpes (herpes simplex strain 2, HSV-2), which are both herpes simplex viruses. Famvir is also used to treat varicella zoster virus (VZV, herpes zoster), which causes chickenpox and shingles in immunocompetent patients.
Famvir is a prodrug which is broken down in the body to penciclovir, which blocks certain enzymes in the virus, preventing the virus from multiplying. This allows the immune system to control the infection.
NowPatient offers famciclovir under the brand name Famvir, or as the generic famciclovir for the treatment of Herpes Simplex virus, genital herpes, and shingles only, following an online consultation with a prescribing clinician.
Key facts of Famvir
- Famvir is used to treat genital herpes, cold sores, and shingles (herpes zoster) in adults
- Famvir has some common side effects which include nausea and vomiting
- It can be dangerous if you take Famvir with certain medications. If you’re not sure if it is safe, discuss this with the prescribing clinician
Famvir contraindications
Famvir may not be suitable for some people. To make sure it’s safe for you, speak to the prescribing clinician before taking Famvir if you:
- Have had an allergic reaction to famciclovir or the inactive ingredient lactose
- Have certain conditions such as galactose intolerance, severe lactase deficiency, or glucose-galactose malabsorption
- Have kidney problems
- Have hepatic problems
- Have a weak immune system
How and where to get Famvir?
You can buy Famvir safely and securely from NowPatient. You can start a consultation today for free and if you qualify for treatment, you only pay for the cost of the medication. Delivery is made to your home or office from our registered pharmacy.
Our service is certified, safe and effective, and we only ever treat conditions. If you book a consultation with a prescribing clinician for the treatment of Herpes Simplex virus, genital herpes, or shingles, you can discuss if Famvir is a suitable treatment option for you.
At the end of the consultation, the clinician will decide if a treatment plan is suitable for you. If it is, the clinician will issue you with a prescription which can then be ordered, paid for and delivered directly to your chosen address by NowPatient.
Dosage and strength for Famvir for Herpes Simplex virus, genital herpes, and shingles
Famvir is available as a tablet, and when used for Herpes Simplex virus, genital herpes, or shingles, it is available in strengths ranging from 250 to 750 mg.
Information about how to take Famvir for Herpes Simplex virus, genital herpes, and shingles
Your dose of Famvir will depend on the condition you are being treated for:
- Herpes Simplex virus – 500mg three times a day for 7 days, or 750mg 1-2 times a day for 7 days
- Genital herpes – 250 mg three times a day for five days or longer if new lesions appear or healing incomplete
- Shingles – 500mg tablets three times a day for 7 days, or 750mg 1-2 times a day for 7 days
If you forget to take a dose, take it as soon as you can. If it is almost time for your next dose, skip the missed dose and take your next dose at your usual time. You should always complete the course of treatment as prescribed by your healthcare professional and read the patient information leaflet provided with your medication.
What happens if you take too much Famvir?
If you take more than prescribed, then it can lead to some unpleasant side effects. You should talk to your doctor or reach out to one of our prescribing clinicians, if you have taken too much Famvir and you experience any of the following side effects:
What are the side effects of famciclovir?
Common side effects include:
- Headache
- Nausea
If you experience any serious side effects, you should contact NHS 111.
If you experience a serious allergic reaction such as anaphylaxis with the signs shown below you should contact emergency services on 999.
- Your lips, mouth, throat or tongue suddenly become swollen
- You’re breathing very fast or struggling to breathe (you may become very wheezy or feel like you’re choking or gasping for air)
- Your throat feels tight or you’re struggling to swallow
- Your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
- You suddenly become very confused, drowsy or dizzy
- Someone faints and cannot be woken up
Always report adverse effects to the MHRA yellow card reporting system. You can read more about this here How and where do I report side effects of my medication? – NowPatient
Information about taking Famvir at the same time as other medications or herbal supplements
There is not enough evidence to suggest there are any drug interactions between herbal supplements and Famvir. In any event, you should let your prescribing clinician know if you are taking any herbal supplements.
Also, speak to your doctor if you are taking certain prescription drugs, in case of drug interactions:
- Cladribine
- Entecavir
- Probenecid
Can Famvir taken for Herpes Simplex virus, genital herpes, shingles be taken long term?
Courses of treatment of Famvir range from 5 to 7 days. If your condition has not improved within this time, speak to your doctor for medical advice.
Is there a herbal Famvir?
No. Herbal Famvir does not exist. If you have been marketed such a formulation, it may be fake.
Can women use Famvir?
Women can take Famvir for the treatment of Herpes Simplex virus, genital herpes, or shingles. However, Famvir is not recommended during pregnancy or if you are breastfeeding as famciclovir may pass into breast milk. Checking with your doctor before taking Famvir.
Should I avoid any particular food or drink when taking Famvir?
You can eat and drink normally when taking Famvir for the treatment of Herpes Simplex virus, genital herpes, or shingles.
What lifestyle changes can I make to help me with Herpes Simplex virus, genital herpes, or shingles.?
Condoms can reduce the risk of getting genital herpes if used correctly, but be aware, a condom will only protect the area of the body it covers. You should also avoid sex while you have outbreaks of sores or blisters.
Shingles develops when the varicella-zoster virus, which originally caused chickenpox, is reactivated in your body, after you have already had chickenpox. There are vaccines such as Shingrix that are now available. Speak to your doctor for advice if you are considering the Shingrix vaccine.
Alternatives to Famvir
Alternatives for the treatment of Herpes Simplex virus, genital herpes, or shingles include other antiviral drugs such as valaciclovir, famciclovir, or aciclovir.
Sources
Medical Disclaimer
NowPatient has taken all reasonable steps to ensure that all material is factually accurate, complete, and current. However, the knowledge and experience of a qualified healthcare professional should always be sought after instead of using the information on this page. Before taking any drug, you should always speak to your doctor or another qualified healthcare provider.
The information provided here about medications is subject to change and is not meant to include all uses, precautions, warnings, directions, drug interactions, allergic reactions, or negative effects. The absence of warnings or other information for a particular medication does not imply that the medication or medication combination is appropriate for all patients or for all possible purposes.
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FAQs
Answers to Popular Questions About Famvir
What is Famvir?
Famvir is a brand-name antiviral medication containing famciclovir, used to treat infections caused by herpes simplex virus (HSV) and varicella-zoster virus (VZV). Famciclovir is the oral prodrug of penciclovir. It is available as 125 mg, 250 mg, and 500 mg tablets. Famvir is used to treat genital herpes (initial and recurrent episodes), cold sores, and shingles. It is a prescription-only medicine in the UK and is considered an alternative to valaciclovir and aciclovir.
How does Famvir work?
Famciclovir is converted in the body to penciclovir, its active antiviral form. Penciclovir is a guanosine nucleoside analogue that is selectively activated in herpes virus-infected cells by viral thymidine kinase. Once activated, penciclovir triphosphate inhibits viral DNA polymerase, blocking viral DNA replication. While penciclovir is less potent than aciclovir in vitro, famciclovir achieves excellent bioavailability and penciclovir has a longer intracellular half-life than aciclovir, potentially providing prolonged antiviral activity.
What is the difference between Famvir and Valtrex?
Both Famvir (famciclovir) and Valtrex (valaciclovir) are effective oral antivirals for herpes infections with similar clinical outcomes. They differ in their active metabolites — famciclovir converts to penciclovir while valaciclovir converts to aciclovir. Penciclovir has a longer intracellular half-life. In practice, both are well-tolerated and equally effective. Valaciclovir is more widely prescribed in the UK and has more data in pregnancy. Famvir may be preferred for patients who do not tolerate valaciclovir or where an alternative is needed.
What is the usual dose of Famvir?
For initial genital herpes: 250 mg three times daily for 5 days. For recurrent genital herpes: 125 mg twice daily for 5 days, or as a single-day regimen of 1 g twice daily. For suppression: 250 mg twice daily. For shingles: 500 mg three times daily for 7 days, ideally started within 72 hours of rash onset. For cold sores: 1.5 g as a single dose. Famciclovir can be taken with or without food. Dose adjustments are needed for renal impairment.
When should I start Famvir?
For best results, start Famvir as early as possible. For recurrent herpes episodes, treatment should begin within 6 hours (ideally) to 24 hours of the first prodromal symptoms (tingling, burning, itching). For shingles, treatment should begin within 72 hours of the rash appearing. Many patients with frequent genital herpes recurrences keep Famvir at home for prompt self-initiated treatment at the first sign of an outbreak.
What are the side effects of Famvir?
Common side effects include headache, nausea, and diarrhoea. Uncommon side effects include dizziness, fatigue, rash, and abdominal pain. Famvir is generally very well-tolerated. Rarely, confusion and hallucinations have been reported, primarily in elderly patients or those with renal impairment. As with all antiviral nucleoside analogues, adequate hydration is advisable, particularly with higher doses.
Can I take Famvir during pregnancy?
There is less safety data for famciclovir in pregnancy compared to aciclovir/valaciclovir. For this reason, valaciclovir or aciclovir are preferred during pregnancy. If you become pregnant while taking Famvir, consult your doctor immediately. Your prescriber may switch you to aciclovir or valaciclovir, which have larger pregnancy safety databases and are recommended by UK guidelines for herpes management in pregnancy.
How can I get a prescription for Famvir?
Famvir can be prescribed by your GP, a GUM clinic, or through online services like NowPatient. It is available as branded Famvir or generic famciclovir. NowPatient provides discreet online consultations with qualified UK prescribers and home delivery, making it convenient for managing herpes infections.
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