Pituitary Hormone Pregnancy: Somatropin-containing products are not recommended during pregnancy or in women of childbearing potential not using contraception — no clinical studies on exposed pregnancies are available and animal studies are insufficient. Caution should be exercised in breast-feeding women (§4.6).

Somatropin (Growth Hormone)

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

Somatropin is recombinant human growth hormone used in children for growth failure due to growth hormone deficiency and several defined conditions such as Turner syndrome, Prader-Willi syndrome, chronic renal insufficiency and small-for-gestational-age short stature.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Growth hormone deficient adults: adult-onset GHD, start at a low dose of 0.15-0.3 mg per day; patients continuing growth hormone therapy after childhood-onset GHD, restart at 0.2-0.5 mg per day. Dose then gradually increased or decreased according to individual requirements as determined by IGF-I concentration

Route: Subcutaneous injection, with the site varied to prevent lipoatrophy

Frequency: Once daily

Max: Adults: the maintenance dose seldom exceeds 1.0 mg per day; in patients above 60 years the maintenance dose seldom exceeds 0.5 mg per day. Children with Prader-Willi syndrome: daily doses of 2.7 mg should not be exceeded

The dosage and administration schedule should be individualised. Treatment goal is an IGF-I concentration within 2 SDS of the age-corrected mean; patients with normal IGF-I at baseline should be titrated up to the upper range of normal, not exceeding 2 SDS. Clinical response and side effects may also guide titration; some patients with GHD do not normalise IGF-I despite a good clinical response and do not require dose escalation. Women may require higher doses than men (men show increasing IGF-I sensitivity over time), so women — especially those on oral oestrogen replacement — risk under-treatment and men over-treatment; the accuracy of the dose should be controlled every 6 months. Dose requirements fall with age: patients above 60 years should start at 0.1-0.2 mg per day and increase slowly, using the minimum effective dose. Where childhood-onset GHD persists into adolescence, treatment should be continued to achieve full somatic development (a normal peak bone mass, T score > -1, is one therapeutic objective in the transition period).

Paediatric dose

Route: Subcutaneous injection, site varied to prevent lipoatrophy

Frequency: Once daily

Max: Prader-Willi syndrome: daily doses of 2.7 mg should not be exceeded

No single per-kg figure applies — the SPC gives an indication-specific dose (most are ranges), so dosePerKg is left null: growth hormone deficiency in children 0.025-0.035 mg/kg/day (0.7-1.0 mg/m2/day, and 'even higher doses have been used'); Prader-Willi syndrome 0.035 mg/kg/day (1.0 mg/m2/day); Turner syndrome 0.045-0.050 mg/kg/day (1.4 mg/m2/day); growth disturbance in chronic renal insufficiency 0.045-0.050 mg/kg/day (1.4 mg/m2/day, higher doses can be needed if growth velocity is too low, with dose correction possibly needed after six months); short children born small for gestational age 0.035 mg/kg/day (1 mg/m2/day) usually until final height is reached. Prader-Willi: do not use in children with a growth velocity of less than 1 cm per year and near closure of epiphyses. Small-for-gestational-age: discontinue after the first year if height velocity SDS is below +1, and discontinue if height velocity is <2 cm/year and (if confirmation is required) bone age is >14 years in girls or >16 years in boys.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients (§4.3)
Any evidence of activity of a tumour — intracranial tumours must be inactive and antitumour therapy completed before starting growth hormone; discontinue if there is evidence of tumour growth
Growth promotion in children with closed epiphyses
Patients with acute critical illness suffering complications following open heart surgery, abdominal surgery, multiple accidental trauma, acute respiratory failure or similar conditions

Side effects

Fluid-retention effects in adults — peripheral oedema, face oedema, musculoskeletal stiffness, arthralgia, myalgia and paraesthesia — common in adults, uncommon in children; generally mild to moderate, arising in the first months and subsiding spontaneously or with dose reduction
Headache (adults and children)
Benign intracranial hypertension
Type 2 diabetes mellitus
Injection-site reactions; gynaecomastia; antibody formation in approximately 1% of patients (low binding capacity, no associated clinical changes)
Leukaemia reported in children (very rare/rare category in the SPC table)

Interactions

Glucocorticoid replacement: somatropin inhibits 11beta-hydroxysteroid dehydrogenase type 1, which may reduce serum cortisol — patients on glucocorticoid replacement for hypoadrenalism may require an increase in maintenance or stress doses after starting somatropin (cortisone acetate and prednisone may be affected more than others) (US NORDITROPIN label §7; the UK SPC §4.5 was not retrieved in this bundle)
Pharmacologic or supraphysiologic glucocorticoid therapy may attenuate the growth-promoting effect of somatropin in paediatric patients (US NORDITROPIN label §7)

Clinical monograph

How it works

It replicates endogenous growth hormone, acting directly and via insulin-like growth factor-1 to stimulate linear bone growth, cell proliferation and protein, lipid and carbohydrate metabolism.

Prescribing in practice

In Prader-Willi syndrome, severe obesity or severe respiratory impairment it carries a risk of sudden death, and it is contraindicated in active malignancy and during acute critical illness, so these must be excluded before and during treatment.
It can unmask or worsen glucose intolerance, intracranial hypertension and slipped capital femoral epiphysis, and reduce thyroxine levels.
It is given by subcutaneous injection and dosing is specialist-directed by weight or surface area; confirm against a children's formulary.

Monitoring

Monitor growth velocity, IGF-1, thyroid function and glucose, and review for headache or visual symptoms, hip or knee pain and, in at-risk children, respiratory status.

Counselling the patient

Rotate injection sites to protect the skin.
Report persistent headaches, vision changes, or a new limp or hip/knee pain.
Attend regular growth and blood-test reviews so treatment can be adjusted.

Evidence & guidelines

NICE technology appraisal guidance supports somatropin for growth hormone deficiency and other defined paediatric growth disorders, with treatment overseen by paediatric endocrinology.

Reference: NICE TA188 (Somatropin for children); NICE TA532 update; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways