Acitab is aciclovir, an antiviral medicine, supplied as dispersible tablets in 200 mg and 400 mg strengths. It treats and suppresses herpes infections — cold sores, genital herpes, chickenpox and shingles. It is not an HIV medicine, despite the category it sits in.
What is Acitab?
Acitab contains aciclovir (also spelled acyclovir). The South African Medicine Price Registry lists two presentations, both Schedule 4:
| Product | Form | Strength |
|---|---|---|
| Acitab-200 DT | Dispersible tablet | Aciclovir 200 mg |
| Acitab-400 DT | Dispersible tablet | Aciclovir 400 mg |
“DT” means dispersible tablet — designed to be dissolved in a little water rather than swallowed whole. That form is useful for children, for older people, and for anyone whose mouth or throat is too sore to swallow a tablet comfortably, which is common in the very infections aciclovir treats.
Aciclovir works with unusual precision. It is inactive as supplied, and is only converted into its active form by an enzyme that herpes viruses produce and human cells do not. Once activated, it jams the viral enzyme that copies viral DNA. Because the activation step happens almost entirely inside infected cells, the medicine concentrates where it is needed and leaves healthy cells largely alone — which is why it is remarkably well tolerated for a medicine that attacks a virus.
The two strengths reflect different uses, not different medicines. Lower doses are typically used for suppression and simple cold sores; higher doses and more frequent dosing for shingles and chickenpox.
What is Acitab commonly used for?
Aciclovir is prescribed for infections caused by the herpes family of viruses:
- Cold sores (herpes simplex on the lips and face), particularly frequent or severe outbreaks.
- Genital herpes — both treating an outbreak and suppressing recurrences with regular lower-dose use.
- Shingles (herpes zoster). Started within 72 hours of the rash appearing, it shortens the illness and may reduce the chance of lingering nerve pain.
- Chickenpox (varicella), especially in adults, teenagers and anyone with a weakened immune system, where the illness tends to be more severe.
- Herpes infections in people with weakened immunity, including those with advanced HIV, transplant recipients and people on chemotherapy.
- Preventing herpes outbreaks during periods of immune suppression.
- Herpes eye infection and other specialist uses, alongside other treatment.
It does not cure herpes. These viruses remain in the body permanently after the first infection, sitting dormant in nerve tissue. Aciclovir controls outbreaks and can suppress them, but nothing available eradicates the virus.
It also has no effect on HIV itself. Aciclovir appears in the antiviral category because it is an antiviral, and it is frequently prescribed to people living with HIV — herpes outbreaks are more frequent and more severe when immunity is reduced. But it is not an antiretroviral and it is never part of HIV treatment itself.
Timing matters more with aciclovir than with most medicines. It works best started at the very first sign of an outbreak — the tingling, itching or burning before a blister appears.
How Acitab fits into this medicine category
| Group | Examples | Target |
|---|---|---|
| Herpes antivirals | Aciclovir (Acitab), valaciclovir | Herpes simplex, varicella zoster |
| Antiretrovirals | Dolutegravir combinations (Acriptega) | HIV |
| Hepatitis antivirals | Entecavir, tenofovir (Hetemcit) | Hepatitis B and C |
| Topical antivirals | Aciclovir cream | Cold sores, applied to the lesion |
| Antibiotics | Penicillins, macrolides | Bacteria — no effect on viruses |
Aciclovir and the antiretrovirals share a shelf and nothing else. See the HIV and antiviral medicines hub.
What to check before using Acitab
Drink plenty of water while taking it. This is the most practical precaution. Aciclovir is cleared by the kidneys and, at higher doses or if you are dehydrated, it can crystallise in them. Good fluid intake largely prevents this.
Tell your doctor or pharmacist if you:
- Have kidney disease or reduced kidney function. The dose usually needs reducing, and this is the main reason aciclovir causes problems.
- Are elderly — kidney function declines with age even without diagnosed kidney disease.
- Take other medicines that affect the kidneys, including regular anti-inflammatories, or take probenecid.
- Have a weakened immune system from HIV, chemotherapy or transplant medicines.
- Are pregnant or breastfeeding. Aciclovir has a long record of use in pregnancy, but the decision should be your clinician’s.
- Are treating a child — it is used in children, dosed by weight and age.
Using it:
- Disperse the tablet in a small amount of water, stir and drink it, then rinse the glass and drink that too so no medicine is left behind.
- Start as early as possible in an outbreak.
- Space doses evenly through the day, including waking hours — aciclovir is often taken four or five times daily, which is more demanding than most medicines and easy to get wrong.
- Complete the course, even once the rash begins to settle.
Follow the dose you were prescribed. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
Aciclovir is generally very well tolerated. The most common effects are nausea, vomiting, diarrhoea, headache, dizziness and tiredness.
Seek medical advice promptly if you notice:
- Reduced urine output, swelling of the ankles, or unusual tiredness — possible kidney effects.
- Confusion, hallucinations, agitation, tremor or unsteadiness. These are uncommon, occur mainly with reduced kidney function or in older people, and are reversible when recognised.
- Unusual bruising or bleeding.
Get emergency help for swelling of the face, lips or tongue, difficulty breathing, or a widespread blistering rash.
Contact your doctor if:
- Shingles affects your face, especially near an eye. This needs urgent assessment — eye involvement can threaten sight.
- The rash is spreading, very painful, or not improving after several days.
- You develop fever, severe headache, neck stiffness, confusion or drowsiness.
- The skin around the rash becomes red, hot, swollen or oozing, suggesting bacterial infection on top.
- Outbreaks keep recurring frequently — suppressive treatment may be a better approach than treating each episode.
- Pain persists after shingles has healed. Post-herpetic neuralgia is common and there are treatments for it.
Related medicine guides
Frequently asked questions
What is Acitab 400 used for? Herpes infections — cold sores, genital herpes, shingles and chickenpox. The 400 mg strength is commonly used for suppression and for higher-dose regimens; 200 mg for lower-dose use.
Is Acitab an HIV medicine? No. It is aciclovir, a herpes antiviral. It has no effect on HIV, though it is often prescribed to people living with HIV for herpes outbreaks.
Does it cure herpes? No. It controls and suppresses outbreaks. The virus stays in the body for life.
How do I take a dispersible tablet? Dissolve it in a small amount of water, stir, drink it, then rinse and drink the rinse water.
When should I start taking it? As early as possible — ideally at the first tingling or burning, and within 72 hours of a shingles rash appearing.
Can I still pass on herpes while taking it? Suppressive treatment reduces transmission risk but does not remove it. Continue other precautions.
Why do I have to take it so many times a day? Aciclovir does not stay in the body long, so frequent dosing keeps levels high enough to work. Spacing doses evenly matters.