Review of Pharmacology - 9E (2015)

Endocrinology
Explanations
1. Ans. (b) Hypoglycemia (Ref: Goodman and Gilman 12/e p1116-1117)
Growth hormone therapy commonly leads to hyperglycemia (not hypoglycaemia)
2. Ans. (c) Bromocriptine (Ref: KDT 6/e p236)
It is an ergot alkaloid and is a dopamine agonist. Dopamine acts as prolactin inhibiting hormone in the brain. Agonism of
dopamine receptors by bromocriptine is responsible for its use in hyperprolactinemia.
3. Ans. (b) Bromocriptine (Ref.: KK Sharma 2/e p550)
Bromocriptine is a D 2
agonist and is useful in hyperprolactinemia by its action to inhibit the release of prolactin.
4. Ans. (d) Glioma (Ref: Katzung 11/e p650, 1081-1082)
• Octreotide is a long acting somatostatin analog. It can be used:
• To decrease secretory diarrhea and other symptoms of carcinoid syndrome and VIPoma.
• For the treatment of diarrhea due to vagotomy, short bowel syndrome and AIDS.
• For treatment and prophylaxis of acute pancreatitis.
• For the management of acromegaly
• For the treatment of islet cell tumors
• For controlling acute bleeding due to esophageal varices
5. Ans. (a) It is effective orally (Ref: Katzung 9/e p1048, KDT 6/e p35)
• Octreotide is the long acting and more potent synthetic analog of somatostatin.
• It can be administered by i.v., s.c. or i.m. routes. It is not effective orally.
• It can be used for
––
Acromegaly
––
Secretory diarrhea associated with carcinoids and AIDS
––
Islet cell tumors
––
Esophageal varices (seen in cases of portal hypertension).
6. Ans. (b) It is longer acting than somatostatin (Ref: KDT 6/e p235)
For details, see text
7. Ans. (d) Nafarelin (Ref: KDT 6/e p239)
Nafarelin is a GnRH agonist. It has no role in acromegaly.
8. Ans. (a) Agonism at D 2
receptors (Ref: KDT 6/e p236)
9. Ans. (b) Immediately reduces gonadotropin secretion (Ref: KDT 6/e p239)
• GnRH agonists like leuprolide, goserelin and nafarelin etc. are used by parenteral route. Continuous administration
of these agents decreases gonadotropin secretion whereas pulsatile administration increases the secretion. When
used continuously even then first few doses cause increased secretion of gonadotropins (LH and FSH) leading to flare
up reaction in prostatic carcinoma.
• GnRH antagonists like cetrorelix and ganirelix are also used by parenteral route but these drugs immediately reduce
gonadotropin secretion.
10. Ans. (a) Bromocriptine (Ref: KDT 6/e p236)
Hyperprolactinemia is caused by D 2
blockers. All the drugs listed are D 2
blockers except bromocriptine which is a D 2
receptor
agonist. It is used in the treatment of hyperprolactinemia.
11. Ans. (a) Bromocriptine (Ref: KDT 6/e p236)
• Symptoms of the patient (amenorrhea, galactorrhea and infertility) points towards the diagnosis of hyperprolactinemia.
• Bromocriptine is a D 2
receptor agonist that can be used in the treatment of hyperprolactinemia (dopamine acts as
prolacting release inhibiting hormone in the hypothalamus).
• Psychosis occurs due to excessive stimulation of D 2
receptors (D 2
blockers are used as typical antipsychotic drugs)
and bromocriptine can precipitate the symptoms in predisposed patients.
General Endocrinology Pharmacology
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