Reasoning GP · Algorithm · 1-page summary
Unsettled baby
For: infants aged 0–6 months with excessive crying, unsettled behaviour or feeding-related distress, in UK primary care. Not for: replacing local paediatric, surgical, safeguarding or sepsis pathways; fever work-up follows the fever in children algorithm, poor weight gain the faltered growth algorithm.
Core rule: colic is a diagnosis of a well, thriving infant with a normal examination — exclude serious illness and safeguarding first, because a sick infant can present only as inconsolable crying, and crying is a recognised trigger for abusive head trauma.
0Stop — call 999 now — do not delay transfer for primary-care investigations
- Weak, high-pitched or continuous cry; reduced responsiveness; bulging fontanelle; non-blanching rash; seizures or focal signs; mottled, pale, blue or ashen; grunting or respiratory distress → 999. Any one is enough.
- Bilious (green) vomiting, marked abdominal distension, peritonism, collapse or failure to pass stool; paroxysmal screaming + legs drawn up + "redcurrant jelly" stool (intussusception) → 999 for immediate emergency paediatric/surgical assessment.
- Pallor + collapse + rigid abdomen, shock or apnoea; change in cry + eye deviation or twitching (consider abusive head trauma) → 999.
1Is the infant ill? — pattern and behaviour between episodes
| Infant | Points to |
|---|---|
| Well between cries | Feeding and thriving → colic likely (peaks 4–8 weeks, improves by 3–4 months) |
| Unwell between cries | Organic cause — pain, infection, metabolic |
| Refusing feeds | Thrush, otitis media, oesophagitis, metabolic |
| Falling centiles | Organic cause or poor intake → Same-day paeds |
2Screen — one row is enough
- Temperature ≥38°C under 3 months, even after vaccination → Urgent hospital/paeds (NG143); not colic.
- Tense irreducible groin swelling; tender swollen testis; hair tourniquet → Immediate emergency surgical/ED assessment; no ultrasound first for torsion.
- Suspected UTI under 3 months → Immediate paediatric referral; urine for urgent microscopy and culture (NG224).
- Persistent projectile non-bilious vomiting under 2 months → Same-day paediatric/surgical assessment + urgent ultrasound.
- Swollen painful limb → Same-day ED + safeguarding. Bruising in a non-mobile infant, fracture, inconsistent history → Same-day paediatrics (immediate if head trauma suspected) + safeguarding lead/Named GP. Parent unable to cope or urge to harm → Same-day risk assessment.
3Assess — undress fully if injury or rash is possible
☐ Temperature, HR, RR, SpO2; CRT ≥3 s = amber ☐ Fontanelle, mouth (thrush, tongue tie, cleft), ears if indicated ☐ Abdomen, hernial orifices, testes, anus, fingers and toes ☐ Skin and limbs ☐ Weigh and plot ☐ Parental mood and coping
No routine tests in typical colic (no urine, stool pH, breath tests); no IgE tests for non-IgE CMPA. GPs do not request skeletal surveys; GP fundoscopy is not definitive.
4Classify — only if the screen is negative
- Infantile colic — well, feeding, normal exam; clinical diagnosis after assessment → reassure and support.
- Reflux — thriving "happy spitter" = GOR → reassure. GORD (troublesome symptoms) → NG1 steps. Crying alone is not reflux.
- CMPA — colic alone is not enough; consider with features in more than one system (eczema, blood or mucus in stool, vomiting, diarrhoea, faltering growth).
- Feeding — under- (latch, tongue tie, over-diluted formula) or overfeeding → feeding review.
- Other — thrush, otitis media, constipation. Uncertain — re-examine; don't anchor on colic.
5Treat today — doses per BNFc and local formulary
- Colic: explain the pattern; ICON — crying is normal, comfort may help, OK to walk away safely, never shake. No routine simeticone, probiotics, antispasmodics, gripe water, lactase or acid suppression.
- Reflux, formula-fed: cut excess volume → smaller, more frequent feeds → thickened formula → then alginate 1–2 weeks (never with thickener). Breastfed: feeding assessment, consider alginate. No PPI/H2RA for crying.
- Suspected non-IgE CMPA: eHF (formula) or maternal cow's-milk exclusion only if indicated (breastfed), 2–6 weeks with dietetic support → reintroduce to confirm.
- Safe sleep: on the back, flat, separate surface; no co-sleeping when exhausted or after alcohol/drugs; never prone, side or inclined.
6Refer and review routinely
- Health visitor for all; lactation consultant; perinatal mental health if depression or severe anxiety; dietitian for CMPA.
- Routine paediatrics: moderate–severe CMPA, complicated GORD, unclear diagnosis; crying beyond 3–4 months → reassess, persistent with no cause → refer.
7Never reassure by
- A "colic" label before examining undressed — digits, groin, testes, skin.
- A normal fontanelle or no neck stiffness — meningitis is not excluded.
- "It's just the vaccine" — fever under 3 months still needs urgent assessment.
- Labelling crying alone as reflux or CMPA — no PPI or formula switch without a clinical indication.
- Accepting an explanation for bruising in a non-mobile infant.
- Not asking about coping — "Has anyone shaken or dropped the baby?" may be appropriate.
8Safety-net — say it, write it, then document it
999 “Call 999 if your baby goes floppy or unresponsive, has a weak, high-pitched or constant cry, looks mottled or blue, has green vomit, a fit, pauses in or difficulty breathing, redcurrant-jelly stool, a tense tummy, a bulging soft spot, a rash that does not fade under a glass, or a tense, tender swelling in the groin or scrotum.”
Same day “Call us or 111 today if feeds drop below half, there are fewer wet nappies, projectile vomiting, blood in the stool, a swollen tummy, unusual sleepiness, or you are struggling to cope. Under 3 months, a temperature of 38°C or more needs urgent hospital assessment.” ICON: “If the crying gets too much, put your baby down safely and walk away for a few minutes — never shake.”
✓Safe to manage in primary care only if — all five, documented
No block 0–2 row applies; temperature recorded
Examined undressed incl. digits, groin, testes, skin
Weighed and plotted; feeding and thriving
Coping and safeguarding asked; ICON and safe sleep given
Written safety-net, HV contact and review documented
Summary of the full Reasoning GP unsettled baby algorithm, which holds the detail. Sources: NICE NG143, NG224, NG1, NG91, CG116, CG89, CG192; iMAP; MHRA (domperidone; Gaviscon Infant SmPC); local formulary; ICON; Working Together to Safeguard Children 2026. Clinical reference — follow local paediatric and safeguarding pathways and check products and doses in the SPC and your local formulary.