Cold Sores (Herpes Labialis):

• Dose: One 200mg tablet five times a day. Your doctor may advise you to take two 200mg tablets (equivalent to one 400mg tablet) five times a day.
• Frequency: Take one dose every four hours while you are awake. For example, at 7 am, 11 am, 3 pm, 7 pm, and 11 pm.
• Duration: Usually for five days, but your doctor may extend this period if needed.
• Important: Start taking aciclovir as soon as you feel the tingling, itching, or burning sensation that usually precedes a cold sore, or when the blisters first appear.

Genital Herpes (Herpes Simplex Genitalis):

• For treating an initial outbreak:
• Dose: One 200mg tablet five times a day. Your doctor may advise you to take two 200mg tablets (equivalent to one 400mg tablet) five times a day.
• Frequency: Take one dose every four hours while you are awake. For example, at 7 am, 11 am, 3 pm, 7 pm, and 11 pm.
• Duration: Usually for five to ten days, or as directed by your doctor.
• For preventing recurrent outbreaks (suppression):
• Dose: One 400mg tablet twice a day. Your doctor may adjust this dose based on how often your outbreaks occur.
• Frequency: Take one tablet in the morning and one in the evening, approximately 12 hours apart.
• Duration: This can be for several months as prescribed by your doctor.
• For treating a recurrent outbreak:
• Dose: One 200mg tablet five times a day. Your doctor may advise you to take two 200mg tablets (equivalent to one 400mg tablet) five times a day.
• Frequency: Take one dose every four hours while you are awake, for five days, or as directed by your doctor.
• Important: Start taking aciclovir as soon as you notice the first signs or symptoms of a recurrence (e.g., tingling, itching, burning, or blisters).

Shingles (Herpes Zoster):

• Dose: Two 400mg tablets (800mg) five times a day.
• Frequency: Take one dose every four hours while you are awake and during the night. For example, at 7 am, 11 am, 3 pm, 7 pm, and 11 pm.
• Duration: For seven to ten days, as directed by your doctor.
• Important: Start taking aciclovir as soon as possible after the shingles rash appears, ideally within 72 hours, to get the maximum benefit.

General Advice:

• Swallow the tablets whole with a glass of water. If you have difficulty swallowing, some tablets can be dissolved in a small amount of water; stir and drink immediately.
• Try to take your doses at the same times each day to maintain a consistent level of the medication in your body.
• Complete the full course of treatment as prescribed by your doctor, even if your symptoms improve before the medication is finished. Stopping early may allow the virus to multiply again.
• Drink plenty of fluids while taking aciclovir to help your kidneys work properly.
• If you miss a dose, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one.
• Inform your doctor or pharmacist if you are taking any other medications, including over-the-counter medicines or herbal supplements, as they may interact with aciclovir.
• Tell your doctor if you have any kidney problems as your dose may need to be adjusted.
• If you experience any unusual side effects, such as allergic reactions (rash, itching, swelling, difficulty breathing), stop taking aciclovir and seek medical attention immediately. Other less serious side effects can occur; consult your doctor or pharmacist if you are concerned.
• It is crucial to consult your doctor or pharmacist for personalized instructions on how to take aciclovir 400mg for your specific condition. They will consider your medical history and the severity of your infection to determine the most appropriate dosage and duration of treatment for you.

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

Common Side Effects:

• Nausea and vomiting (especially after IV administration)
• Diarrhoea
• Headache (mild to moderate)
• Dizziness or light-headedness

Less Common Side Effects:

• Skin rash or hives
• Fatigue
• Abdominal pain
• Dehydration (with high IV doses)

Rare Side Effects:

• Neurotoxicity (confusion, tremors, hallucinations)
• Kidney problems
• Low platelet count (thrombocytopenia)
• Elevated liver enzymes

For complete safety information, consult the patient leaflet. Contact your doctor if you experience any concerning side effects.

If you have a damaged or weakened immune system (immunocompromised) you should seek medical advice before taking Aciclovir and at any time you experience a cold sore or other infection.

If you are elderly, renally impaired, pregnant or breastfeeding, you should seek medical advice before taking Aciclovir.

Get emergency medical help if you have signs of an allergic reaction to this medication. These include:

• Hives
• Dizziness
• Fast or pounding heartbeats
• Wheezing
• Difficult breathing
• Swelling of your face, lips, tongue, or throat.

It is important that you let us know which prescription, over-the-counter medicines and recreational drugs you are currently taking. You must also tell us about any other medical conditions that you currently have (or had in the past). This will help us ensure the prescribed medication is safe and appropriate for you to take.

For full information on warnings, medication interactions and contraindications, refer to the Patient Information Leaflet. Please read all packaging and the Patient Information Leaflet before taking any new medicine and inform our clinical team or your GP of medicines you are taking or intend to take.