Aciclovir tablets are a well-established treatment for cold sores and other herpes simplex infections, but they're not the only option, and they're not without trade-offs. This guide weighs the genuine advantages against the real limitations, and compares tablets to cream and valaciclovir, so you can make an informed choice rather than assume tablets are automatically the best option simply because they're systemic.
Key things to know
- Aciclovir is an antiviral, not an antibiotic. It won't treat bacterial infections.
- Oral tablets provide systemic treatment; clinical studies suggest aciclovir can modestly shorten healing time when started early in an outbreak.
- Aciclovir 200mg is the standard oral treatment strength used for herpes simplex infections. 400mg tablets are also available but may be used for different regimens or circumstances.
- Valaciclovir converts to aciclovir in the body with better absorption, allowing less frequent dosing.
Is Aciclovir an Antibiotic?
No, and this is worth clarifying directly. Aciclovir is an antiviral medicine, targeting the herpes simplex virus specifically. Antibiotics treat bacterial infections and have no effect on viruses. Confusing the two matters practically: taking an antibiotic wouldn't help a cold sore, and aciclovir won't help a bacterial infection like impetigo, they're different drug classes for different types of infection entirely. If you are ever unsure whether a skin condition is viral or bacterial, that's exactly the kind of question worth getting a proper assessment for, rather than guessing based on symptoms that can sometimes look superficially similar.
Advantages of Aciclovir Tablets
Weighed fairly against the alternatives, tablets offer several genuine benefits worth understanding before you decide what's right for you:
- Oral treatment delivers aciclovir systemically, rather than only to the area where a cream is applied. This makes oral treatment useful for herpes infections where systemic antiviral treatment is indicated.
- Clinical studies suggest aciclovir can modestly reduce the duration of herpes outbreaks when treatment is started early.
- Established safety record: aciclovir has been used clinically for several decades, with an extensive, well-understood safety profile.
- Suitable for suppressive therapy: regular suppressive treatment can significantly reduce the frequency of recurrent outbreaks in appropriate patients, something topical cream is not typically used for.
- Aciclovir is available in different tablet strengths, allowing prescribers to select an appropriate formulation and regimen for the condition being treated.
Disadvantages and Limitations
It is just as important to be honest about the drawbacks, since no treatment is without trade-offs:
- Benefit is generally greatest when treatment is started as early as possible, ideally during the early symptoms or when lesions first appear.
- Systemic exposure: since tablets work throughout the body, they carry a different side effect profile than a topical product applied only to the affected area.
- Cost over repeated courses: while generic aciclovir is affordable, frequent outbreaks needing repeated courses add up, worth factoring into your overall cost if recurrence is common.
- Side effects can include nausea, vomiting, diarrhoea, headache and dizziness.
- Kidney problems are an important consideration, particularly in people with existing renal impairment. Aciclovir is cleared through the kidneys, so the dose may need adjusting when kidney function is reduced. Adequate hydration is also advised, particularly with higher oral doses.
None of these should be read as reasons to avoid aciclovir tablets outright; they're factors worth weighing against the potential benefits above when deciding what's right for your specific situation.
For more information on side effects and dosing, see our Aciclovir Tablets Benefits Guide and Aciclovir Side Effects Guide.
Tablets vs Cream: Which Suits You Better
This is one of the most common decisions people face when choosing cold sore treatment, and it genuinely depends on your specific situation rather than one option being universally superior:
| Aciclovir Tablets | Aciclovir 5% Cream | |
|---|---|---|
| Coverage | Systemic / Oral | Topical |
| Typical role | Used when oral antiviral treatment is appropriate | Used for local cold sore treatment |
| Suppressive treatment | Yes, oral aciclovir can be used for recurrent HSV suppression | Not typically used for long-term suppression |
| Dosing | Depends on the condition and prescribed regimen | Usually applied several times daily according to product instructions |
For a mild, localised cold sore, a topical treatment may be sufficient for some people. Oral aciclovir is used when systemic antiviral treatment is appropriate, including for certain herpes infections and for suppression of recurrent herpes simplex. The right option depends on the type and severity of the infection, recurrence pattern and individual circumstances.
Aciclovir vs Valaciclovir
Valaciclovir is converted into aciclovir in the body after absorption and has higher oral bioavailability, meaning more of the dose reaches your system. This allows less frequent dosing than aciclovir in many treatment regimens.
For some people, this convenience genuinely matters, particularly if remembering multiple daily doses is difficult. The two medicines are closely related because valaciclovir is converted to aciclovir in the body. The practical difference is often dosing frequency and cost, although the appropriate choice depends on the infection and individual circumstances.
If you have struggled with remembering multiple daily doses of aciclovir in the past, that is a genuine, practical reason to discuss valaciclovir with your prescriber, rather than assuming the two are simply interchangeable at the same price point. Conversely, if cost is your main concern and you are comfortable with a more frequent dosing schedule, generic aciclovir remains a fully effective, lower-cost choice.
Which Strength: 200mg or 400mg?
For treating herpes simplex infections, the usual adult oral regimen in the UK product information is 200mg aciclovir five times daily at approximately four-hour intervals, omitting the night-time dose. Treatment is generally continued for five days, although severe initial infections may require longer treatment.
Aciclovir 400mg tablets are also available and are used in other regimens, including some suppressive-treatment schedules or particular clinical circumstances. The tablet strength should not be used to determine your dose yourself. Follow the regimen prescribed for your infection.
If you miss a dose, take it when you remember unless it is nearly time for the next dose. Do not take a double dose to make up for a missed one.
Ready to compare your options with a prescriber? Start your free cold sore consultation.
Available Treatments for Genital Herpes
| Treatment | Price |
|---|---|
| Aciclovir Tablets | From £12.99 |
| Aciclovir 5% Cream | From £8.99 |
| Valaciclovir | From £18.99 |
| Valtrex | From £34.99 |
Prices update live and may change. Aciclovir tablets are prescription-only medicines in the UK, which can be arranged through online healthcare after a free online consultation. You will complete an online consultation for review by a UK-registered prescriber, and approved orders are sent through our discreet delivery service.
Medical Disclaimer
This page provides general information comparing aciclovir tablets, cream and valaciclovir. It is not a substitute for personalised medical advice, diagnosis or treatment. The appropriate treatment depends on the type of herpes infection, your symptoms, recurrence pattern, kidney function and other individual factors. Always follow the dosing instructions provided by your prescriber or pharmacist. If you have questions about your treatment or possible interactions with other medicines, speak to a pharmacist, prescriber or GP.
