Endocrine Disorder Drugs

exam 1

Somatropin is an analog for what hormone?

Growth hormone

Somatropin clinical use

SC injection for pituitary or hypothalamic dwarfism or to treat AIDS induced wasting syndrome

Somatropin adverse effects

Well tolerated

Intracranial hypertension, arthralgia, myalgia, peripheral edema, hyperglycemia

Mecasermin is an analog for what?

IGF-1

Mecasermin MOA

Stimulates IGF-1 receptors and improves growth (bone) and metabolic effects (increase in muscle mass, decrease body fat)

Mecasermin use

SC injection for Laron dwarfism

Mecasermin adverse effects

Hypoglycemia, intracranial hypertensions

What should patients eat with Mecasermin?

Carbohydrate rich meal

In what disease state should somatropin and mecasermin not be administered?

Patients with malignancies or past malignancies

Octreotide, Lanreotide, and pasireotide are analogs for what?

Somatostatin

Octreotide, Lanreotide, and pasireotide use

SC injection for gigantism or acromegaly

Octreotide, Lanreotide, and pasireotide side effects

GI disturbances, gall stones, bradycardia, conduction abnormalities

Bromocriptine and cabergoline are agonists for what?

Dopamine

Dopamine is not a peptide and drugs are given orally

Bromocriptine and cabergoline use

Acromegaly, but mainly used for hyperprolactinemia

Bromocriptine and cabergoline adverse effects

Nausea, headache, orthostatic hypotensions

Less effects with cabergoline due to higher selectivity for D2 receptors

Pegvisomant is an antagonist for what?

Growth hormone receptor

Pegvisomant use

SC injection for Acromegaly and gigantism

Pegvisomant side effects

increased liver enzymes

monitor liver function → may increase risk of adenomas → requires annual pituitary MRI

Desmopressin is an analog for what?

Vasopressin

Desmopressin use

Central diabetes insipidis, bedwetting, bleeding disorders

Why can desmopressin be used for bleeding disorders

Releases von Willebrand factor and clotting factor 8 from vascular endothelium

Why is desmopressin effective in Central DI?

Stimulates V2 at a higher affinity, allowing for more antidiuretic effect and less effect on blood vessels.

Desmopressin adverse effects

GI disturbances, hyponatremia, allergic reactions

Conivaptan and Tolvaptan are antagonists for what?

Vasopressin receptor

Conivaptan and Tolvaptan use

Syndrome of inappropriate ADH secretion (SIADH)

Conivaptan and Tolvaptan adverse effects

dry mouth, increased thirst and urination, hypernatremia

Pitocin is the analog for what?

Oxytocin

Pitocin use

initation of labor, to produce milk let down, reduce or prevent post partum hemorrhage

Pitocin adverse effects

Uterine hyperstimulation, hypotension, hyponatremia

Levothyroxine (T4)

preferred agent for thyroid replacement

long half life

Liothyronine (T3)

More potent so faster onset but shorter duration of action

higher incidence of cardiac adverse effects

Liotrix (T4/T3)

more potent than levothyroxine as it has both T4 and T3

Desiccated thyroid

variable hormone concentrations

Adverse effects of thyroid preparations

Increased risk of cardiac events like angina, arrhythmia, and heart failure

In what populations should we avoid using T3?

People with cardiac disease

Drug interactions of thyroid preparations

Enzyme inducers (rifampin, phenytoin, phenobarbital, carbamazepine) increase clearance of T3 and T4

Thioamides (methimazole and PTU) MOA

inhibition of organification and coupling

PTU also inhibits T4 to T3 conversion

Since synthesis is inhibited but not release, clinical response is 3-4 weeks

Thioamides use

Methimazole is used for thyrotoxicosis, caution in pregnancy

PTU is used for thyroid storm or thyrotoxicosis in pregnancy

Thioamides adverse effects

skin rash, nausea, GI distress, agranulocytosis, hypothyroidism

PTU → hepatitis

Iodides (potassium iodide) MOA

inhibition of organification and coupling and proteolysis and release, and reduction of thyroid vascularity and size

Iodides (potassium iodide) use

Thyroid storm, due to quick onset of action (2-7 days because of release inhibition)

Preop prep for thyroidectomy

Iodides (potassium iodide) adverse effects

Iodism - rash, metallic taste, increased salivation, mucous membrane ulcerations

Caution for iodides

should not be used as a monotherapy due to transient and reversible effect of the medication

Radioactive iodine MOA

Beta and gamma emitter → destroys thyroid

Radioactive iodine use

hyperthyroidism

Radioactive iodine adverse effects

Hypothyroidism, ophthalmopathy

Contraindicated in pregnancy and lactation

Beta blockers MOA

block beta adrenoreceptors in the heart, decreasing HR and contractility

can inhibit T4 to T3 conversion at very high doses (unusual)

Beta blockers use

decrease heart rate and contractility, which is increased in hyperthyroidism

Beta blockers adverse effects

Bradycardia, hypotension, bronchospasm in asthmatics