Pituitary And Thyroid Drugs

Question 1

GH usage and mechanism

Answer 1

GH regulates IGF1 for normal growth, lipid and carbohydrate metabolism
Used for children that fail to grow (renal insufficiency, small for gestational age case), for adults having AIDs, malabsorption problems bcz of intestinal resection, for athelets to gain muscle mass

Question 2

Adverse effects of somatotropin or GH

Answer 2

In children: pseudotumor cerebri, progression of edema, scoliosis, hyperglycemia, slipped capital femoral epiphysis
In adults: peripheral edema, migraine, arthralgia

Question 3

Somatotropin usage

Answer 3

GH deficiency in children or genetic disorders like Turner’s, Noonan and prader willi

Question 4

If children have growth failure and are unresponsive to GH, we give them

Answer 4

Mecasermin a recombinant of IGF1 is taken parenterally
Side effects: hypoglycemia ( prevented by eating before taking it)

Question 5

Normal function of somatostatin

Answer 5

Inhibits Glucagon, gastrin, insulin and GH

Question 6

Octreotide and lanreotide

Answer 6

Somatostatin analog used for acromegaly, gastrinoma, glucagonoma and carnoid tumors, variceal bleeding
Taken subcutaneously 2-4 times daily or slow release IM every 4 weeks
Side effects: GI distrubances, gallstones, bradycardia

Question 7

Bromocriptine

Answer 7

Inhibits prolactin in hyperprolactinemia or galactorrhea
In high doses causes GH secrting tumors

Question 8

Pegvisomant

Answer 8

Mutant GH that can cross link receptors but cannot activate them and is used for acromegaly

Question 9

Normal LH function

Answer 9

Released by the anterior pituitary, in men leads to testosterone release and in women forms androsteinidone from cholesterol in theca cells to help in synthesis of estradiol

Question 10

Normal FSH function

Answer 10

Released by anterior pituitary, in men stimulates spermatogenesis regulation, in women forms estradiol from androsteinidone in granulosa cells

Question 11

Ovulation induction protocol using gonadotropins

Answer 11

-administration of GnRH agonist or antagonist for inhibition of gonadotropin production
-daily injections of a preparation with FSH activity (menotropin or FSH analogs) for follicles development
-injection of LH or LH analog human chorionic gonadotropin (hCG) for oocyte maturation
All administered parenterally

Question 12

Menotropin

Answer 12

FSH+LH purified from urine of postmenopausal women

Question 13

Urofollitropin or follitropin alpha and beta

Answer 13

FSH and analogs
Purified from urine or recombinant of human FSH respectively

Question 14

Lutropin or hCG

Answer 14

Recombinant of LH or placental protein supporting the corpus luteum during early pregnancy actuvating LH receptors (purified or recombinant) respectively

Question 15

In ovulation induction, we can use GnRH agonist or antagonists what are they?

Answer 15

Leuprolide agonist also used for endometriosis, uterine leiomyomata and in men for prostate cancer
Ganirelix, cetrorelix, degarelix (used for prostate cancer) antagonists
Side effects: hot flushes, sweats, headache and in men also gynecomastia induced libido, decreased hemantocrit, reduced bone density

Question 16

2 hormones secreted by posterior pituitary

Answer 16

Oxytocin and vasopression ADH
Oxytocin can be given by IV for inducing labor or reinforcing it
ADH creats aquaporin channels to reabsorb water and cause vasoconstriction

Question 17

Atosiban

Answer 17

Antagonist of oxytocin used as tocolytic (for preterm labor)

Question 18

Desmopressin

Answer 18

Agonist of V2 receptor activation (causing water reabsorbtion) taken orally, nasally or parenterally for diabetes inspidus, mild hemophilia A (van willerband disease)

Question 19

Conivaptan/tolvaptan

Answer 19

Drugs given to onset the fluid retention associated with excess of vasopressin because of acute HF or hyponatremia

Question 20

Thyroid function regulation

Answer 20

Thyroid functions with iodine availability and thyrotropin (TSH)
TSH release is inhibited by high levels of thyroid hormones (- feedback)

Question 21

Mechanism and effects of T3 and T4

Answer 21

They bind to to intracellular receptors controlling expression of genes
They affect normal growth and development of nervous, skeletal and reproductive systems, control metabolism of fats, carbs, proteins and vitamins

Question 22

T3 and T4 drugs

Answer 22

Liothyromine and synthetic levothyroxine respectively

Question 23

Thyrotoxicosis symptoms

Answer 23

It is the hyperthyroidism syndrome seen with warm, moist skin, sweating, tachycardia, increased stroke volume, cardiac output and pulse pressure. Dyspnea, increased apetite, nervousness, weakness, increased deep tendon reflexes, menstrual irregularity, decreased fertility, weight loss and exophthalmous in graves’ disease

Question 24

Hypothyroidism symptoms

Answer 24

Pale, cool, puffy skin, srnsation of being cold, bradycardia, decreased stroke volume, cardiac output and pulse pressure.
Pleural effusions, hypoventilation and CO2 retention, reduced appetite, lethargy, slowing mental processes, stiffness, decreased deep tendon reflexes, infertility, decreased libido, impotence and oligospermia, weight gain.

Question 25

Methimazole, propylthiouracil (PTU)

Answer 25

Taken orally and inhibit thyroid hormone synthesis by blocking peroxidase catalyzed reactions. They work for 3-4 weeks.
Effective for young patients with small glands and mild disease.
Toxicity: skin rash, vasculitis, agranulocytosis, hypoprothrombinemia, liver dysfunction, aplastic anemia. Methimazole is a teratogen aplasia cutis and ptu is taken in 1st trimester of pregnancy.

Question 26

Lugol’s solution and saturated solution of potassium iodide

Answer 26

Lugol’s is a combination of iodine and potassium iodide
They inhibit iodination of thyrosine and thyroid hormone release and decrease size and vascularity of the hyperplastic thyroid gland. They are used for management of thyroid storm and prepare patients for resection of hyperactive thyroid
Onset of action: 2-7 days
Adverse effects: rash, drug fever, metallic taste, bleeding disorders, anaphylactic reactions.

Question 27

Radioactive iodine

Answer 27

Taken up and concentrated in the thyroid
It can cure thyrotoxicosis without surgery but cannot be taken by pregnant wonen or nursing women.
High doses->hypothyroidism