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Pituitary Hormone Pregnancy: Contraindicated in pregnancy

Somatropin (Growth Hormone)

Brand names: Genotropin, Humatrope, Norditropin, Omnitrope, Saizen

Adult dose

Dose: 0.15-0.3 mg/day SC (adult GH deficiency)
Route: Subcutaneous injection
Frequency: Once daily (evening)
Max: Titrated to IGF-1 levels; typically under 1 mg/day
Evening administration mimics physiological GH secretion during sleep

Paediatric dose

Dose: 0.025-0.05 mg/kg/day mg/day/kg
Route: Subcutaneous injection
Frequency: Once daily (evening preferred)
Max: 0.067 mg/kg/day (Turner syndrome, Prader-Willi)
Growth hormone deficiency: 0.025-0.035 mg/kg/day SC once daily. Turner syndrome: up to 0.05 mg/kg/day. Prader-Willi syndrome: 0.035 mg/kg/day. Small for gestational age (SGA): 0.035 mg/kg/day. Rotate injection sites. Dose adjusted based on growth velocity and IGF-1 levels. Specialist initiation only (NICE TA188)

Dose adjustments

Renal

Use with caution; dose adjustment may be required in severe impairment

Hepatic

Use with caution in severe hepatic impairment

Paediatric weight-based calculator

Growth hormone deficiency: 0.025-0.035 mg/kg/day SC once daily. Turner syndrome: up to 0.05 mg/kg/day. Prader-Willi syndrome: 0.035 mg/kg/day. Small for gestational age (SGA): 0.035 mg/kg/day. Rotate injection sites. Dose adjusted based on growth velocity and IGF-1 levels. Specialist initiation only (NICE TA188)

Clinical pearls

  • NICE TA188: Somatropin recommended for children with growth hormone deficiency, Turner syndrome, Prader-Willi syndrome, and short stature in SGA (if no catch-up by age 4)
  • Treatment continues until final height achieved (epiphyseal closure) or growth velocity under 2 cm/year
  • Monitor for slipped capital femoral epiphysis — child presenting with hip or knee pain during treatment warrants urgent assessment
  • Intracranial hypertension: if papilloedema or severe headache develops, discontinue and refer urgently
  • All prescribing through specialist paediatric endocrinology; not initiated in primary care

Contraindications

  • Active malignancy
  • Closed epiphyses (for growth promotion)
  • Acute critical illness (relative)
  • Prader-Willi syndrome with severe obesity and respiratory impairment

Side effects

  • Injection site reactions
  • Headache
  • Intracranial hypertension (benign — papilloedema; rare)
  • Slipped capital femoral epiphysis
  • Fluid retention and oedema
  • Insulin resistance / hyperglycaemia
  • Scoliosis progression

Interactions

  • Glucocorticoids (impair growth response — use minimum corticosteroid dose)
  • Insulin (somatropin may reduce insulin sensitivity — adjust dose)
  • Sex steroids (may accelerate bone maturation)

Monitoring

  • Growth velocity (height every 3-6 months)
  • IGF-1 and IGFBP-3 levels
  • Thyroid function (GH can unmask hypothyroidism)
  • Fasting glucose / HbA1c
  • Bone age X-ray annually
  • Fundoscopy if headache or visual symptoms

Reference: BNF for Children; NICE TA188 (Somatropin for children); NICE TA532 update; BNF 90. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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