Drugs affecting Pituitary

a) ADH (Vasopressin) affecting drugs

  • Desmopressin

An ADH mimic that is the most effective treatment for neurogenic diabetes insipidus

– It has higher activity on V2 receptors in collecting tubule rather than V1 receptors

– Not effective for nephrogenic form of diabetes insipidus

– Also used for nocturnal enuresis by reducing night-time urine production

– Treats Von Willebrand disease as it stimulates production of Factor VIII


  • Terlipressin

This is an ADH mimic with a higher affinity for V1 receptors.

– It causes vasoconstriction of arterioles especially supplying the gut.

Used to treat noradrenaline resistant hypotension and portal hypertension.


  • VaptansConivaptan + Tolvaptan

These are antagonists of ADH receptors, which are used to treat SIADH

– Conivaptan blocks both V1a and V2 receptors non-specifically to treat SIADH

– Tolvaptan is a  selective V2 receptor antagonist to treat SIADH


b) Oxytocin drugs

  • Oxytocin – Used for the induction and maintenance of labour as stimulates uterine contraction

– Also stimulates milk ejection from the breast

– First line drugs to control postpartum uterine bleeding


Side effects: As very similar to ADH, can cause water reabsorption + hypertension




a) Drugs influencing Prolactin

Prolactin secretion is also affected by drugs used on the central nervous system which affect dopaminergic activity. These will include antipsychotics + Antidepressants + Anxiolytics


As prolactin secretion is inhibited by Dopaminergic neurones, drugs which try to decrease prolactin secretion often try to stimulate the dopaminergic system.


  • Bromocriptine + Cabergoline

These are dopamine D2 agonists which can act within the central nervous system

– They are used to inhibit prolactin secretion in prolactin-secreting tumours and galactorrhoea


b) Drugs influencing Growth Hormone

  • Somatotropin

These is a synthetic version of growth hormone which is administered via injection

– Used to stimulate growth in replacement therapy in people with GH deficiency and Turner syndrome


  • GH antagonistsPegvisomant

This is a GH antagonist that is used specifically for the treatment of acromegaly.

– It opposes the actions of growth hormone but will not help to shrink the pituitary tumour.


  • Somatostatin analogsOctreotide + Lanreotide (longer-acting analog)

– These mimic the role of somatostatin to inhibit growth hormone release

– Used to treat acromegaly

– Also used to counter diarrhea through the inhibition of GI secretions, slowing of GI motility and inhibition of gallbladder secretion.

– Used to treat VIP-secreting tumours like gastrinoma, glucagonoma


Side effects: Vitamin B12 Deficiency due to decreased release of intrinsic factor

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