Sleep after vaccinations
They had their jabs this morning and tonight has been miserable. This is common, it is short, and it is the clearest example of a disruption you should absorb rather than respond to.
3 min read
A mild reaction after immunisation is expected and is a sign the immune system is doing what it should. Common effects include a raised temperature, irritability, a sore or red leg, sleepiness in the day and unsettled nights.
Most of it lasts twenty-four to forty-eight hours. Some vaccines, particularly the MMR, can produce a delayed reaction about a week to ten days afterwards, which surprises people who thought they were clear.
What to do
Extra comfort, no new habits. Hold them, feed them, stay longer. Do not introduce a sleep condition you would not want to keep.
Paracetamol if advised. Ask your nurse or GP at the appointment. For some vaccines - the MenB in particular - paracetamol is specifically recommended in advance and afterwards.
Fluids and feeds as usual. Feeding more often is common on the day. Let them.
Bedtime earlier. They are likely to be more tired than usual, and an early night reduces the damage.
Do not move naps around. They may sleep longer in the day. Let that happen for one day and go straight back to the usual schedule the next.
Do not change the plan
This is the shortest and most predictable disruption in the first year. Two bad nights is not information about your schedule, your settling method or anything else. Absorb it and carry on.
If you were in the middle of settling work, pause for two nights and resume. Nothing is lost.
Two nights is not a pattern. It is the immune system doing its job, and it needs no adjustment from you.
Planning the day around them
A small amount of planning removes most of the difficulty. Book the appointment for late morning where you can, so the reaction peaks in the afternoon rather than at two in the morning. Keep the rest of the day quiet with nothing else in it. Feed on demand - many babies want more milk and less food for a day.
Move bedtime earlier by half an hour, because they will be more tired than usual and an overtired baby handles a sore leg considerably worse. And expect the following day to be a little off as well; two days is the usual span rather than one.
The delayed ones
Most reactions arrive within twenty-four to forty-eight hours, but the MMR is different: a mild fever and unsettled nights can appear about a week to ten days afterwards, and again around two weeks for the rubella component. Families who thought they were clear are frequently caught out by this.
It is worth writing the date on the calendar so that a run of bad nights ten days later has an obvious explanation. Otherwise it looks like a regression arriving from nowhere, and people restructure a schedule in response to something that will be over in two days.
When to stop troubleshooting
Contact your GP or call 111 for a temperature over 39°C, a fever lasting more than two days, a fever in a baby under three months, inconsolable crying for more than three hours, a baby who is difficult to rouse, a fit or seizure, or a rash that does not fade under pressure. Signs of a severe allergic reaction - swelling of the face, difficulty breathing - need an ambulance, though these are very rare and usually occur within minutes at the clinic.
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