Synopsis
Diagnose adult growth-hormone deficiency in the right clinical context and deliver monitored specialist replacement only when benefit and safety criteria are met.
- Adult growth-hormone deficiency is most credible after pituitary or hypothalamic disease, surgery, radiotherapy, trauma, genetic disease or multiple other pituitary deficits; fatigue and central adiposity alone are not diagnostic.
- Recognised effects include impaired quality of life, reduced exercise capacity and lean mass, increased visceral fat, adverse lipids and reduced bone density, but each is nonspecific and alternative causes remain important.
- A random growth-hormone concentration cannot diagnose deficiency because normal secretion is pulsatile; IGF-1 supports the assessment but a value inside the reference range does not reliably exclude disease.
Key red flags
Hypotension, vomiting, hypoglycaemia, hyponatraemia or reduced consciousness in pituitary disease suggests cortisol deficiency; give emergency glucocorticoid treatment before pursuing growth-hormone testing.
Investigation priorities
Establish whether hypothalamic-pituitary disease is sufficiently likely to justify specialist dynamic testing.
Management branches
Symptoms occur in a person with pituitary disease, cranial treatment or another credible hypothalamic-pituitary risk.
- Confirm the anatomical and treatment history, review every pituitary axis, medicines, sleep, mood, nutrition and systemic disease, and document objective morbidity.
- Measure IGF-1 in an assay-aware context, recognising influences that can lower it and that a normal result may not exclude organic disease.
Key medicines
SomatropinUse the selected licensed subcutaneous preparation at a low individual starting dose, then titrate gradually to age-adjusted IGF-1, response and adverse effects under specialist care.
Hydrocortisone replacementEstablish the current physiological endocrine regimen and stress-dose education before provocative testing or somatropin when ACTH deficiency is present.