Pituitary & Hypothalamus Pharm

Drug Class: Somatotropin

growth hormone analog

Drug Class: Pegvisomant

growth hormone receptor antagonist

Drug Class: Octreotide

somatostatin analog

Drug Class: Lanreotide

somatostatin analog

Drug Class: Pasireotide

somatostatin analog

Drug Class: Bromocriptine

D2 agonist

Drug Class: Cabergoline

D2 agonist

Drug Class: Desmopressin

ADH analog

Drug Class: Tolvaptan

ADH receptor antagonist

Drug Class: Conivaptan

ADH receptor antagonist

Drug Class: Democlocycline

ADH receptor antagonist

Mechanism: Somatotropin

binds growth hormone receptor to initiate JAK-STAT pathway

Mechanism: Mecasermin

stimulates IGF1 to improve growth

Mechanism: Pegvisomant

antagonism of growth hormone receptor

Mechanism: Somatostatin Analogs

agonism at somatostatin receptors with a longer duration of action

Mechanism: D2 Agonists

D2 agonism of anterior pituitary lactotrope cells to decrease prolactin secretion

Mechanism: Desmopressin

mimics ADH

Mechanism: ADH Receptor Antagonists

antagonism of ADH receptors

P/D: Somatotropin

influences hepatic production of IGF1 to increase muscle mass and linear growth

increases lipolysis

decreases insulin sensitivity and glucose uptake

What are the 1st generation somatostatin analogs?

octreotide and lanreotide

What is the 2nd generation somatostatin analog?

pasireotide

What medications are ergot alkaloids?

bromocriptine and cabergoline

P/D: Desmopressin

more potent, long acting, and V2 selective

given PO, IV, SC, or as a nasal spray

minimal pressor activity (no vasoconstriction)

P/D: Tolvaptan

selective at V2 receptor

P/D: Conivaptan

acts on V1 and V2 receptors

given IV

P/D: Demeclocycline

non-selective

General A/E: Somatotropin

hyperglycemia and new onset DM

hypothyroidism

Peds A/E: Somatotropin

pancreatitis

gynecomastia

nevus growth

pseudotumor cerebri

SCFE and scoliosis progression

edema

Adult A/E: Somatotropin

myalgia and arthralgia

carpal tunnel

peripheral edema

A/E: Mecasermin

hypoglycemia

A/E: Desmopressin

dilutional hyponatremia

A/E: Vasopressin

vasoconstriction

CAD precipitation

A/E: ADH Receptor Agonists

nephrogeneic diabetes insipidus

dry mouth and thirst

hypotension

A/E: Demeclocycline

bone and teeth abnormalities in peds <12

Use: Somatotropin

pediatric growth failure

growth hormone deficiency

wasting in HIV patients

short bowel syndrome (patients also getting nutrition)

Use: Mecasermin

growth hormone resistance

Drug Class: Mecasermin

recombinant human IGF1

Use: Pegvisomant

acromegaly

Use: Somatostatin Analogs

acromegaly

ACTH secreting tumor (cushing’s)

portal HTN

secretory diarrheas

GI tumors

Use: Octreotide

acute variceal bleeds

GI tumors treated by somatostatin analogs

somatostatinoma

carcinoid syndrome

gastrinoma

glucagonoma

VIPoma

Actions of somatostatin

inhibitor paracrine factor

inhibits release of GH, TSH, glucagon, insulin, gastrin, secretin, CCK, GIP

Use: Bromocriptine

prolactinoma

reversal of neuroleptic malignant syndrome

acromegaly

Use: Cabergoline

idiopathic hyperprolactinemia

acromegaly

Past uses for D2 agonists

Parkinson’s and lactation suppression

Role of dopamine

prolactin inhibition

Role of prolactin

milk production in lactation

Use: Desmopressin

central diabetes insipidus

von willebrand disease

nocturnal enuresis

hemophilia A

Use: ADH Receptor Antagonists

syndrome of inappropriate ADH (SIADH)

ADH Receptor V1a,b

located in CNS and vasculature

1A: vasoconstriction

1B: ACTH release

ADH Receptor V2

regulate von willebrand factor and factor 8 to promote clotting

enhance renal H2O permeability in collecting tubule —> increased H2O absorption —> anti-diuresis

Treatment of Nephrogenic Diabetes Insipidus

thiazide diuretic (induce natriuresis)

amiloride (if induced by lithium)

Treatment of Central Diabetes Insipidus

desmopressin

Drugs Blunting Desmopressin Effects

lithium and demeclocycline

Cautions when using Desmopressin

angina, HTN, HF from ECF expansion and increased preload