Vaccines at 4 months: DPT-HB-Hib 3 & Oral Polio 4 (bOPV 4) & Injectable Polio (IPV)
The 4-month visit closes the primary series: DPT-HB-Hib 3, Oral Polio 4, and, for the first time, the injectable polio vaccine (IPV). After today your baby's primary protection is complete until MR at 9 months.
ⓘ This page is educational, not medical advice. For specific needs, consult your pediatrician or midwife.
Vaccines given at 4 months
-
DPT-HB-Hib 3
- Protects against
- The third and final DPT-HB-Hib primary dose. After it, protection against diphtheria, pertussis, tetanus, hepatitis B, and Hib is at full strength, maintained later by the 18-month booster.
- How it is given
- Injection into the thigh (intramuscular).
- Side effects
- Same as earlier doses: mild fever and swelling for 1–2 days. A warm compress and age-appropriate paracetamol as advised by the nurse help.
- Availability
- Free at posyandu and puskesmas; also available from pediatric (IDAI) clinics.
-
Oral Polio 4 (bOPV 4)
- Protects against
- Poliomyelitis (polio). The fourth dose strengthens gut immunity against wild poliovirus.
- How it is given
- Drops given directly into the mouth (oral).
- Side effects
- Almost no side effects.
- Availability
- Free at posyandu and puskesmas.
-
Injectable Polio (IPV)
- Protects against
- All poliovirus types. IPV builds blood-level immunity on top of the oral drops, part of the global polio eradication strategy.
- How it is given
- Injection into the thigh or arm (intramuscular).
- Side effects
- Mild soreness and redness at the injection site for 1–2 days.
- Availability
- Free at posyandu and puskesmas.
- Note
- Given together with Oral Polio 4 at the 4-month visit.
Why it matters at this age
The third DPT-HB-Hib dose locks in full protection against five diseases, while IPV builds blood antibodies against all three poliovirus types. That is a second layer on top of gut immunity from the oral drops. The combination is the global endgame strategy against polio.
What to bring to posyandu
Bring the KIA book and mark this visit as the end of the primary series. Your baby will get two injections (thigh/arm) plus oral drops. No feeding 30 minutes around the drops. Double-check the records: every dose from birth to 4 months should now be filled in.
Frequently asked questions
What is the difference between IPV and the polio drops?
The oral drops (bOPV) contain live weakened virus working in the gut; IPV contains inactivated virus working through the bloodstream. They complement each other. Drops interrupt transmission in the community, IPV guarantees each child individual protection.
After 4 months, when is the next vaccination?
A gap until 9 months for MR 1 (measles–rubella). Use the break to audit the KIA book; if any dose was missed, this is the best window to catch up before MR.
My baby only ever got the oral drops, no DPT-HB-Hib. What now?
You can still proceed. Start the DPT-HB-Hib series as soon as possible with at least 4 weeks between doses. Puskesmas staff will tailor a catch-up schedule to your baby's current age.
Never miss a dose. Track it and get reminders
Mark given doses in the WeLoveOurBaby app and get automatic reminders for the next due date, calculated from your child's birth date.
Start tracking for freeNext age: 9 months
- Kemenkes RI, Ayo Sehat: childhood immunization routine schedule
- IDAI, Immunization Schedule for Children Aged 0–18 Years (2024 recommendation)
Last reviewed: 2026-08