Birth Vaccines
Oral Polio Vaccine (OPV) Side Effects in Babies
Most babies have no reaction to polio drops at all — no injection, no sore spot, and at most a little brief fussiness.
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
- Birth, 6/10/14 weeks + polio rounds
- How it's given
- 2 drops by mouth — no needle
- Protects against
- Polio (paralysis)
- Typical reaction
- Usually none; brief fussiness at most
- If baby spits it out
- The dose is repeated — it's safe
The oral polio vaccine (OPV) is the two-drop vaccine given straight into your baby's mouth — at birth, alongside the 6, 10 and 14 week doses, and during India's Pulse Polio immunisation days. It has helped make India polio-free since 2014.
Because OPV is swallowed rather than injected, it skips the most common vaccine complaints entirely: there's no needle, no sore leg and no local swelling. Most babies show no reaction whatsoever, which is why paediatricians often call it one of the easiest vaccines on the schedule.
What the oral polio vaccine is
OPV contains live, severely weakened poliovirus that trains the gut's immune system to block the real virus. It is given as two drops on the tongue — quick, painless and needle-free.
In India, OPV is given at birth (the 'zero dose'), with the primary series doses, and repeatedly during Pulse Polio campaign days. Extra campaign doses are safe — there is no harm in a child receiving additional OPV drops during national or sub-national rounds. Injectable polio vaccine (IPV) works alongside OPV in the schedule to give the strongest combined protection.
Common OPV side effects
Genuinely noticeable reactions are the exception rather than the rule. When they happen, they look like this:
No reaction at all (most babies)
The most common outcome after polio drops is nothing — no fever, no fussiness, no change in feeding. An uneventful day is the norm, not a sign the vaccine didn't work.
Brief fussiness or a grimace at the taste
Some babies pull a face, cry briefly or seem mildly unsettled after the drops. This passes within minutes to hours.
Spitting up or a small vomit
Babies occasionally spit up soon after the drops. If your baby vomits most of the dose within about 10 minutes, the vaccinator simply gives it again — repeating is safe.
Mild, loose stool (occasionally)
A slightly loose motion or two in the following day can occur. Persistent diarrhoea, blood in stool or signs of dehydration point to another cause and deserve a check.
Low-grade fever (uncommon)
A mild temperature is possible but infrequent. When babies do get fever on vaccination day, it's more often from injectable vaccines given at the same visit.
What's usually normal after polio drops
- No visible reaction at all — the most common outcome.
- A brief cry or grimace at the taste of the drops.
- Spitting up a little of the dose (the vaccinator repeats it if it's most of the dose, within minutes).
- Normal feeding within the hour — breastfeeding straight after the drops is fine.
- One or two slightly looser stools over the next day.
- Being given OPV again during Pulse Polio days even if a dose was recent — extra doses are safe.
How long OPV side effects last
- Fussiness or unsettled behaviour: typically minutes to a few hours.
- Mild loose stools: usually settle within a day.
- Low-grade fever, if it occurs at all: usually less than 24 hours.
- There is no injection site, so there is nothing to heal — no soreness, lump or redness to monitor.
Home care after polio drops
OPV needs almost no aftercare — these simple points cover it:
Feeding
- Breastfeed or bottle-feed normally — there is no need to withhold feeds after the drops.
- If your baby vomits most of the dose within about 10 minutes, tell the vaccinator — the dose is simply repeated.
- Offer extra feeds if your baby seems mildly unsettled; sucking is a great soother.
Comfort & watching
- Treat the day as completely normal — play, naps and outings can continue.
- If injectable vaccines were given at the same visit, follow the home-care advice for those injection sites too.
- Keep your baby's vaccination card safe and record the dose, including Pulse Polio campaign doses.
Warning signs — see a doctor urgently
Serious reactions to OPV are extremely rare, but seek urgent care for:
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).
- Sudden floppiness, unresponsiveness or your baby being very hard to wake.
- New weakness of an arm or leg, or a noticeable loss of movement in the weeks after vaccination (vaccine-associated paralysis is extraordinarily rare — roughly one in a few million doses — but it is the reaction doctors watch for).
- High fever with your baby looking seriously unwell.
- Persistent vomiting or signs of dehydration — very few wet nappies, dry mouth, sunken eyes.
Call your doctor immediately — or go straight to the nearest emergency department.
🩺 Find a paediatricianFor breathing difficulty, facial swelling or unresponsiveness, go straight to the nearest emergency department.
When to call your paediatrician
- Diarrhoea that continues beyond a day or two, or any blood in the stool.
- Fever that lasts more than 24–48 hours after vaccination day.
- Feeding much less than usual for more than a few hours.
- You're not sure whether a repeated dose is needed after your baby vomited the drops.
- Any change in your baby that worries you — trust your instinct and call.
Frequently asked questions
My baby vomited right after the polio drops. Is the dose wasted?
If a baby vomits most of the dose within about 10 minutes, the vaccinator gives the drops again — this is standard practice and completely safe. If the vomit happens later than that, the dose has usually been absorbed and doesn't need repeating.
Can I breastfeed immediately after OPV?
Yes. Feeding immediately before or after polio drops is fine and does not reduce the vaccine's effectiveness. Feeding is also a great way to settle a fussy baby after the visit.
My child already had OPV — should they still get drops on Pulse Polio day?
Yes. Every child under 5 should receive drops during Pulse Polio rounds regardless of previous doses. Extra OPV doses are safe and boost community protection.
Why does my baby get both OPV drops and a polio injection (IPV)?
The two work together: IPV builds strong protection in the blood, while OPV builds gut immunity that stops the virus spreading. Getting both is intentional and recommended, not a duplication error.
Do polio drops cause fever or diarrhoea?
Usually not. A mild temperature or a slightly loose stool can occasionally follow, but most babies have no reaction. Marked fever or persistent diarrhoea after vaccination day is more likely to have another cause — check with your doctor.
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
- MoHFW — Pulse Polio Programme
Next review due: 6 January 2027.
Continue on ParentVibes
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.
Read our Medical Disclaimer, Editorial Policy and Medical Review Policy.