Aciclovir 400mg Tablets

Directions

Note: Always follow your doctor’s instructions and the patient leaflet.

• Dosage and Frequency:

  • Herpes simplex: 200mg 5 times daily for 5 days

  • Shingles: 800mg 5 times daily for 7 days

  • Suppression: 400mg twice daily (as prescribed)

• Application: Swallow whole with water, spaced evenly throughout the day

• Safety Reminders:

  • Start treatment at first signs of symptoms

  • Stay hydrated

  • Do not skip doses

Storage:

• Store below 25°C

• Keep in original packaging

• Keep out of reach of children

Ingredients

• Active Ingredient:

  • Aciclovir (200mg, 400mg or 800mg depending on pack)

• Key Excipients:

  • Lactose monohydrate

  • Sodium starch glycolate

  • Magnesium stearate

Side Effects

Common side effects:

• Headache

• Nausea

• Diarrhoea

• Fatigue

Serious side effects (rare):

• Allergic reaction (rash, swelling, difficulty breathing)

• Confusion or hallucinations in elderly patients

Seek urgent medical advice if serious reactions occur.

Warnings

• Contraindications:

  • Allergy to aciclovir or similar antivirals

  • Kidney impairment (may require monitoring)

• Pregnancy/Breastfeeding:

  • Safe when advised by a doctor

• Drug Interactions:

  • Caution with probenecid or other nephrotoxic drugs

• Age Restrictions:

  • Safe for adults and children as directed

Aciclovir 400mg Tablets are prescription antiviral medicines used to treat and prevent infections caused by the herpes simplex and varicella-zoster viruses. These viruses cause conditions such as cold sores, genital herpes, shingles (herpes zoster), and chickenpox. Aciclovir works by targeting the virus directly at the site of replication, which helps shorten the duration and severity of symptoms while reducing the risk of further transmission.

Doctors also prescribe Aciclovir to prevent recurring outbreaks in people who experience frequent episodes of genital herpes or cold sores. Moreover, it is often recommended for patients with weakened immune systems to protect them from potentially serious viral infections.

Because this medicine is effective at both treating active infections and preventing future episodes, it offers flexibility for short- or long-term use. Taking the tablets at the first sign of an outbreak can help control symptoms before they worsen.

How It Works

Aciclovir belongs to a group of medicines called antiviral agents. It interferes with the virus’s ability to replicate its DNA. Specifically, it becomes active once inside infected cells and blocks the function of viral DNA polymerase. As a result, the virus cannot multiply, allowing the body’s immune system to regain control and clear the infection more effectively.

Why Choose Aciclovir

Patients choose Aciclovir for its proven efficacy, especially in managing herpes-related infections. It is well tolerated and has a well-established safety record. Because it works selectively on virus-infected cells, it rarely causes side effects in healthy tissues. Furthermore, it is one of the few antivirals available in oral tablet form, offering a convenient and non-invasive treatment option.

For people at risk of frequent outbreaks or those recovering from more severe infections, Aciclovir offers both protection and symptom relief. When taken as prescribed, it can significantly reduce downtime and discomfort caused by herpes viruses.

Important Note

Aciclovir 400mg Tablets are Prescription Only Medicines (POM) in the UK.
You should only take this medication under the supervision of a licensed healthcare provider. Always follow the dosage and course length exactly as directed, and speak to your GP or pharmacist if you have concerns about side effects or other health conditions.