6–14 Week Vaccines
IPV (Polio Injection) Side Effects in Babies
A slightly sore thigh and maybe a small red spot — the injectable polio vaccine is one of the gentlest shots your baby gets.
Written and fact-checked by the ParentVibes editorial team against WHO, IAP, CDC and NHS immunisation guidance. Not yet reviewed by a named clinician.
Quick facts
- Usually given
- 6 & 14 weeks (NIS); 6/10/14 weeks (IAP)
- How it's given
- Injection into the thigh
- Protects against
- Polio (paralysis)
- Typical reaction
- Brief soreness ± small red spot
- Usually settles in
- 1–2 days
IPV (injectable polio vaccine) is the polio shot given into your baby's thigh during the primary vaccination series. Alongside the familiar oral polio drops (OPV), it is a key part of how India keeps children protected against polio — a disease that can cause lifelong paralysis.
Many parents ask why a baby needs both drops and an injection for the same illness. The two are a deliberate team: the injection builds strong protection in the bloodstream, while the drops build immunity in the gut that helps stop the virus spreading in the community. IPV itself is a remarkably gentle vaccine — most babies barely react to it, and because it's an inactivated vaccine, it cannot give your baby polio.
What the injectable polio vaccine is
IPV is an inactivated (killed) vaccine — it contains poliovirus that has been completely destroyed so it can no longer infect anyone. This means it trains the immune system to recognise polio without any risk of causing the disease. It is given as a small injection into the thigh muscle in infancy.
In India, IPV is part of the National Immunization Schedule (given at 6 and 14 weeks) and the IAP schedule (which adds a 10-week dose). It is almost always given at the same visit as other injections such as pentavalent and PCV, so it helps to know that reactions on vaccination day often reflect the whole set of shots together, not IPV on its own.
Drops and injection — both on purpose
Getting IPV (injection) as well as OPV (drops) is not a mistake or a duplicate. Each protects your baby in a different way, and paediatricians recommend both for the strongest, most complete polio protection.
Common IPV side effects
IPV has a very mild profile. When there is any reaction at all, it is nearly always small and short-lived.
Brief soreness at the injection site
The thigh where the injection was given may be a little tender for a day or so. Your baby might cry when the spot is touched during nappy changes or when picked up.
A small red spot or slight swelling
A small area of redness or mild firmness at the injection site is common and usually fades within a day or two. It is a normal local response, not a sign of infection.
Occasional low-grade fever
A mild temperature can occur in the first day, though it is uncommon with IPV alone. When babies do run a fever on vaccination day, it is often linked to the other injections given at the same visit.
Mild fussiness or reduced feeding
Some babies are a little unsettled or feed slightly less on the day of the shot. This typically passes with extra cuddles and feeds and is back to normal by the next day.
Reactions from the whole visit
Because IPV is usually one of several injections at a single appointment, any fever or fussiness you notice may come from the combination. Care for your baby based on how they feel, not on which single vaccine caused it.
What's usually normal after IPV
IPV reactions are among the mildest of any baby vaccine. These are the signs of a normal response:
- No reaction at all — a completely uneventful day is very common.
- A tender thigh or a small red spot at the injection site for a day or two.
- A brief, mild temperature in the first 24 hours that settles on its own.
- A little extra fussiness or a short dip in appetite on vaccination day.
- Normal feeding, alertness and wet nappies returning by the next day.
- Slightly more reaction when IPV is given with other injections at the same visit.
How long IPV side effects last
- Soreness and redness at the injection site: usually 1–2 days.
- Low-grade fever, if it occurs at all: typically within the first 24 hours.
- Fussiness or reduced feeding: generally settles by the next day.
- There is nothing that needs long-term watching — IPV leaves no lasting mark or lump to monitor.
Short and simple
IPV recovery is measured in a day or two, not weeks. If soreness or fever lingers well beyond that, or your baby seems increasingly unwell, check with your paediatrician.
Home care after IPV
IPV needs very little aftercare — comfort and gentle attention to the injection site are usually all it takes.
Comfort & soothing
- Feed on demand — breastfeeding during or just after the shot helps ease your baby's pain.
- Offer cuddles, gentle rocking and skin-to-skin contact if your baby is unsettled.
- Move the leg gently during play; keeping it lightly active can ease stiffness at the site.
Injection site & fever
- A cool, clean, damp cloth held gently on the sore spot for a few minutes can soothe it.
- Dress your baby in light layers and don't over-bundle if they feel warm.
- If your baby is uncomfortable with fever, use paracetamol only in the dose your doctor has advised for your child's weight — never aspirin.
Warning signs — see a doctor urgently
Serious reactions to IPV are very rare, but seek urgent care if you notice:
Seek urgent medical care if your child has
- Signs of a severe allergic reaction — difficulty breathing, swelling of the face, lips or tongue, or widespread hives (usually within minutes to an hour of the shot).
- A high fever of 40°C or above, or a fever in a baby under 3 months old.
- Sudden floppiness, unresponsiveness, or a baby who is very hard to wake.
- Inconsolable, high-pitched crying that continues for more than about three hours.
- Your baby looking seriously unwell — very pale, limp, or not their usual self.
- Spreading redness, warmth or pus at the injection site.
Call your doctor immediately — or go straight to the nearest emergency department.
🩺 Find a paediatricianIf your baby is struggling to breathe, has facial swelling or is unresponsive, go to the nearest emergency department immediately — don't wait for an appointment.
When to call your paediatrician
Not an emergency, but worth a call or a visit:
- Fever that lasts more than 24–48 hours or keeps returning.
- The injection site becomes more red, warm or swollen after the first couple of days rather than settling.
- Feeding stays reduced beyond the first day.
- You're unsure whether a symptom is from IPV or one of the other vaccines given that day.
- Anything about your baby that worries you — trust your instinct and call.
Frequently asked questions
Can the IPV injection give my baby polio?
No. IPV is an inactivated (killed) vaccine — the poliovirus in it has been completely destroyed and cannot cause infection. It teaches the immune system to fight polio without any risk of the disease itself.
Why does my baby get both polio drops and a polio injection?
They work as a team. The IPV injection builds strong protection in the blood, while the OPV drops build immunity in the gut that helps stop the virus spreading. Paediatricians recommend both together for the most complete protection — it isn't a duplicate dose.
Is it normal for my baby's thigh to be sore after IPV?
Yes. Mild soreness and a small red spot at the injection site are the most common IPV reactions and usually fade within a day or two. Gentle movement of the leg and feeding for comfort help. See a doctor if the area becomes increasingly red, hot or swollen.
Does IPV cause fever?
Only occasionally, and usually just a mild temperature. Because IPV is given with other injections at the same visit, a fever on vaccination day often comes from the combination rather than IPV alone. Care for your baby based on how they feel.
My baby had drops during a Pulse Polio round — do they still need IPV?
Yes. The campaign drops (OPV) and the scheduled IPV injection do different jobs, so your baby needs both as per the schedule. Extra OPV drops during campaigns don't replace the IPV doses on the immunisation card.
Your next steps
Track your baby's vaccines
Enter your baby's birth date to get a personalised vaccine timeline with reminders, so no dose slips.
Open Vaccination TrackerVaccination schedule India
The full IAP-style immunisation chart from birth to the teen years, explained in plain language.
See the full scheduleFind a paediatrician
Worried about a reaction, or due for the next dose? Find a trusted paediatrician near you.
Find a pediatricianRelated vaccine guides
Sources
- WHO — Vaccine safety and side effects
- Indian Academy of Pediatrics (IAP) — Immunization guidelines
- CDC — Possible side effects from vaccines
- NHS — NHS vaccinations and when to have them
- WHO — Polio vaccines position paper
- CDC — Polio vaccine (IPV) information
Next review due: 6 January 2027.
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Medical disclaimer
This page is educational information about common vaccine reactions and is not a substitute for medical advice, diagnosis or treatment. Every child is different — always follow the guidance of your paediatrician or vaccination centre. If your child has trouble breathing, swelling of the face or throat, a fast heartbeat, hives all over, dizziness or weakness soon after a vaccine, or seems seriously unwell at any point, seek emergency medical care immediately. When in doubt, always get your child checked — it is never a waste of anyone's time.
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