Chickenpox is one of those childhood illnesses most parents will deal with at some point. In healthy young children it's usually mild, runs its course in a couple of weeks, and is far more an itchy nuisance than a danger. But the management has a few specifics that genuinely matter – particularly the fact that ibuprofen should not be used. Here's what to expect, what to do, and the small set of situations where chickenpox stops being a "manage it at home" illness.
Healthbooq provides parents with evidence-based guidance on common childhood illnesses including chickenpox, with practical management advice grounded in current NHS and UKHSA guidance.
What Chickenpox Looks Like
Chickenpox is caused by the varicella-zoster virus. It typically starts with one to two days of fever, headache, and feeling generally rotten before the rash appears. Then come the spots: small red dots that rapidly turn into fluid-filled blisters, then crust over.
The pattern that distinguishes chickenpox is that new spots appear in crops over three to five days, so at any one time you'll see spots at different stages – some red and freshly emerging, some blistered, some crusted. The rash usually starts on the trunk and spreads to the face, scalp, and limbs. Inside the mouth and on the genitals are common sites too, and these can be particularly uncomfortable.
The illness is most contagious from two days before the rash appears until every spot has crusted over – typically five to six days after the rash starts. A child can return to nursery or school once all spots are crusted, regardless of total number.
Management
The most important single point: ibuprofen should not be used in chickenpox. Studies have linked ibuprofen use during chickenpox with serious bacterial skin infections, including necrotising fasciitis and severe group A streptococcal infection. NHS guidance is unambiguous on this. Paracetamol at the appropriate dose for the child's age and weight is safe and works well for fever and discomfort.
The itch is the symptom that drives everyone mad. What helps:
- Calamine lotion dabbed on spots – cooling, mildly anti-itch, cheap
- Antihistamines – chlorphenamine (Piriton) is licensed from one year, sedating, and helpful at bedtime when itch interferes with sleep
- Cool baths (lukewarm, not hot – heat makes itch worse). Adding bicarbonate of soda or oat-based bath products soothes some children
- Short, clean fingernails to minimise damage and infection from scratching. For young children, mittens or socks over the hands at night reduce sleep scratching
- Loose, cool cotton clothing – tight or warm clothing aggravates the itch
Plenty of fluids and paracetamol for fever round out the basics.
Which Children Need Medical Attention
For most healthy children under ten, chickenpox runs its course at home. The groups who need medical assessment:
- Babies under four weeks – chickenpox in newborns can be serious
- Immunocompromised children – those on chemotherapy, immunosuppressive medication, or with conditions affecting immune function
- Children with severe or spreading skin infection on the spots – look for spreading redness around spots, increased warmth, swelling, or pus. These signs of bacterial superinfection need same-day assessment
- A child who looks much sicker than chickenpox alone should make them – very lethargic, breathing problems, persistent high fever after the rash, severe headache, repeated vomiting, or a stiff neck
- Children with significant eczema – chickenpox spots can be particularly severe in eczematous skin
Antiviral treatment with aciclovir is used for high-risk groups and is most effective when started within 24 hours of the rash appearing. If you have a child in a high-risk group who's been exposed to or develops chickenpox, get medical advice the same day.
Chickenpox Vaccination
Chickenpox vaccination is not currently part of the routine UK childhood immunisation schedule, although the JCVI has been re-examining this and a change may come. It's standard in many other countries (US, Germany, Australia). Children at high medical risk – siblings of immunocompromised children, for instance – can be offered vaccination through NHS referral.
For other families, the vaccine is available privately. The decision is reasonable either way: the case for it is sparing your child from a miserable week or two, the case against is that natural infection produces durable immunity and the illness is usually mild.
Key Takeaways
Chickenpox (varicella) is one of the most common childhood illnesses, usually mild in healthy children under ten years but occasionally causing complications. The distinctive blister-like rash appears in crops over several days and resolves within ten to fourteen days. Ibuprofen should not be used for chickenpox — it is associated with serious bacterial superinfection in this setting. Management is with paracetamol for fever and discomfort, calamine lotion or antihistamines for itch, and keeping nails short to minimise scratching. Chickenpox is highly contagious until all spots have crusted over.
