Module 8: Drugs Related to Hypothalamic and Pituitary Function

Question 1

Hypothalamus and Pituitary

Answer 1

 Related anatomically and functionally
 Regulate all bodily processes
 15 hormones and regulatory factors

Question 2

Overview of Hypothalamic
and Pituitary Endocrinology

Answer 2

Hormones of the anterior pituitary
 Growth hormone (GH)
 Corticotropin
 Thyrotropin
 Follicle-stimulating hormone (FSH)
 Luteinizing hormone (LH)
 Prolactin

Hormones of the posterior pituitary
 Oxytocin
 Antidiuretic hormone

Question 3

Growth Hormone

Answer 3

Biologic effects
 Promotes growth
 Promotes protein synthesis
 Carbohydrate metabolism

Physiology
 Regulation of release
 Biologic effects
 Promotion of protein synthesis
 Effect on carbohydrate metabolism

Pathophysiology
 Deficiency
* Pediatric: Short stature, slowed growth, mental function not impaired, replacement therapy
* Adult: Reduced muscle mass

 Excess
* Pediatric: Gigantism (7 to 9 feet tall)
 Treatment: Removal of pituitary gland
* Adult: Acromegaly if epiphyses already closed
 Treatment: Surgery, radiation, or drugs (octreotide
[Sandostatin, Sandostatin LAR Depot], lanreotide [Somatuline Depot], and pegvisomant [Somavert], bromocriptine [Parlodel], pasireotide [Signifor]

Therapeutic uses
 Pediatric growth hormone deficiency
 Pediatric non–growth-hormone-deficient short stature
 Pediatric short stature associated with Prader-Willi
syndrome (PWS)
 Adult growth hormone deficiency

Adverse effects and interactions
 Hyperglycemia
 Neutralizing antibodies
 Carpal tunnel syndrome
 Fatality in patients with Prader-Willi syndrome
 Interaction with glucocorticoids

Question 4

Prolactin

Answer 4

Produced by anterior pituitary
 Stimulates milk production after parturition
 Effects of hypersecretion (excessive secretion)
 Females: Amenorrhea, galactorrhea, infertility,
possible delay of puberty in girls
 Males: Reduced libido and potency, galactorrhea,
possible delay of puberty in boys

Treatment for hypersecretion
 Suppression of prolactin release
* Cabergoline [Dostinex]
* Bromocriptine [Parlodel]

Question 5

Other Anterior
Pituitary Hormones

Answer 5

Thyrotropin
 Thyroid-stimulating hormone (TSH)

Corticotropin
 Adrenocorticotropic hormone (ACTH)

Gonadotropins
 Follicle-stimulating hormone (FSH)
 Luteinizing hormone (LH)

Question 6

Antidiuretic Hormone

Answer 6

ADH (also known as vasopressin)
 Promotes renal conservation of water
 Works on the collecting ducts of the kidney to
increase their permeability to water
 Produced in the hypothalamus

Therapeutic uses
 Diabetes insipidus
 Cardiac arrest
 Postoperative abdominal distention
 Preparation for abdominal radiography
 Desmopressin for nocturnal enuresis (bedwetting)
 Hemophilia A
 Von Willebrand’s disease

Question 7

ADH Use with Diabetes Insipidus

Answer 7

Diabetes insipidus
 Deficiency of ADH
* Polydipsia (excessive thirst)
* Excretion of large volumes of dilute urine
 Treatment: ADH replacement
* Desmopressin (agent of choice)
* Vasopressin
 Adverse effects
* Water intoxication
* Excessive vasoconstriction

Question 8

Acromegaly

Answer 8

Growth hormone excess
 Pituitary adenoma
 Clinical manifestations

Treatment
 Surgery
 Radiation
 Somatostatin

Question 9

Somatropin [Humatrope]

Answer 9

Somatostatin analogs (octreotide and lanreotide)
are the most effective drugs for suppressing GH
release
 Identical to human GH
 Intramuscular (IM) or subcutaneous (subQ)
administration