My 10-month-old son has a fever of 103.5
For reference only. Not medical advice.
Question
My 10-month-old son has a fever of 103.5°F. He has refused all milk since morning, cries without tears, his fontanelle looks sunken, and he hasn't had a wet diaper in over 9 hours. He is lethargic and whimpering.
Should we wait for our pediatrician tomorrow morning, or go to the pediatric emergency room immediately? What should we do on the way?
Answer
PASS — typing the draft into the reply now.
Call your local emergency number now and take your son straight to the pediatric emergency department — do not wait until your pediatrician opens tomorrow morning. The combination of a high fever, no wet diaper for over 9 hours, a sunken fontanelle, crying without tears, refusing all milk, and lethargy is treated as severe dehydration with possible serious infection (sepsis) in an infant under 1, and a child with these signs can get worse quickly over the next few hours.
On the way / while you travel
- Keep him warm and hold him in the position he has chosen on your lap; do not force him to lie flat if he is more settled upright.
- Offer small sips of milk, formula, or water only if he is fully awake and can swallow well. Do not pour or syringe fluids into a sleepy or whimpering baby — that is an aspiration risk. Do not wipe him down with alcohol.
- Do not give any new medicine at home to bring the fever down on the basis of this card; if a fever-reducing medicine has already been directed by his clinician or by the product label, follow that label only. The fever number itself is not the problem — his appearance is.
- Note when the fever started, the highest reading and the time you took it, when he last drank well, when he last had a wet diaper, when he last seemed himself, and his immunisations. The team in the E will want these.
Why this is not a wait-until-morning situation
- A sunken fontanelle, no urine for 9 hours, and tears that have stopped are signs the source uses for severe dehydration, not mild.
- Lethargy and whimpering in a febrile young infant are listed as "the child looks seriously unwell — suspected sepsis," which is treated as needing assessment in the first hour, not the first morning.
- Waiting overnight risks the dehydration tipping into shock. A short ride to the pediatric emergency department now is safer than a longer wait at home.
What to bring / be ready to say in the E
- Age in months, birth history if known, immunisation status.
- The temperature readings with times, how you took them, and any fever medicine already given (names only — do not adjust a dose on your own).
- Last feed, last wet diaper, last wet nappy with stool, number of vomits.
- Anyone sick at home, any recent travel, any known allergies.
- The question worth asking: what specifically should bring us straight back, and over what hours should I see improvement.
You did not name a place in your message
I have not been given a country or city for you, so I have not printed any phone digits from memory — that is a hard rule here. In your reply, tell me which country or city you are in, and I will hand you the verified local emergency-service number and the nearest pediatric emergency door on the next turn.
| Now | Not |
|---|---|
| Call local emergency services and head to pediatric E | Wait until the pediatrician opens in the morning |
| Keep him warm, hold him in his chosen position | Force fluids into a sleepy or whimpering baby |
| Bring the timeline (fever, last drink, last wet diaper) | Try to bring the fever down with new medicine at home |
—
_I do not diagnose, I do not calculate a dose, and a clinician on the spot has to see him. Coverage: red flags only — local emergency-service numbers, individual medicine doses, and an in-person exam are not in scope here._
_Source: `child.md` (severe dehydration / shock with vomiting and diarrhoea; suspected sepsis; febrile child) and `fever.md` (look-seriously-unwell / suspected sepsis)._