Материал: 2016_Kaplan_USMLE_Step_1_Lecture_Notes_Pharmacology

Learning Objectives

Use knowledge of bisphosphonates and teriparatide to solve problems

BISPHOSPHONATES: ALENDRONATE AND OTHER

DRONATES

λMechanisms: stabilize hydroxyapatite bone structure and also induce osteoblasts to secrete inhibitors of osteoclasts →↓ bone resorption →↓ progression of osteoporosis

λClinical uses:

–Established use in Paget disease

–Efficacy in postmenopausal osteoporosis depends on individual drug, but alendronate is effective and with HRT causes ↑ bone mineral density (BMD).

–Alendronate is drug of choice for glucocorticoid-induced osteoporosis

λSide effects:

–Etidronate and pamidronate → bone mineralization defects

–Gastrointestinal distress, including esophageal ulcers (alendronate)

TERIPARATIDE

λMechanism: recombinant DNA PTH analog

λClinical use: once daily to stimulate osteoblasts and new bone formation

λContinuous infusion would stimulate osteoclast activity

λUsed for less than 2 years; may ↑ risk of osteosarcoma

Chapter Summary

λThe bisphosphonates decrease bone resorption and slow the progress of osteoporosis. Alendronate is effective for treatment of postmenopausal and steroid-induced osteoporosis. The principal potential side effects are gastrointestinal distress and esophageal ulcers.

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Section VIII λ Endocrine Pharmacology

1.A 70-year-old man is diagnosed with benign prostatic hyperplasia (BPH), and his physician is considering drug treatment of the condition. It was decided that the drug finasteride will be used. The effects of finasteride will result in a decrease in the synthesis of what substance?

A.Epinephrine

B.Norepinephrine

C.Dihydrotestosterone

D.Testosterone

E.GnRH

2.Which of the following statements is accurate regarding drug management of hyperthyroidism?

A.The actions of thyroid peroxidase are inhibited by I131

B.Propylthiouracil inhibits the conversion of thyroxine to triiodothyronine

C.Methimazole is unable to cross the placental barrier

D.Iodide salts can be used for long-term management

E.The iodination of tyrosyl residues to form MIT and DIT are inhibited by beta blockers

3.What drug is useful to distinguish neurogenic from nephrogenic diabetes insipidus?

A.Amiloride

B.Demeclocycline

C.Desmopressin

D.Hydrochlorothiazide

E.Lithium

4.The release of insulin from pancreatic beta cells would most likely be stimulated by which of the following?

A.Clonidine

B.Norepinephrine

C.Diazoxide

D.Glipizide

E.Hypoglycemia

5.When used at higher doses than commonly employed for other purposes, what drug can effectively inhibit steroidogenesis in a variety of tissues?

A.Flutamide

B.Misoprostol

C.Clomiphene

D.Tamoxifen

E.Ketoconazole

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Chapter 6 λ Endocrine List and Practice Questions

6.In a patient with type 2 diabetes, which drug mimics the action of incretins to augment glucose-dependent insulin secretion?

A.Acarbose

B.Glucagon

C.Exenatide

D.Metformin

E.Rosiglitazone

7.To supplement other oral type 2 diabetes medication, a patient is prescribed a drug to inhibit the intestinal absorption of carbohydrates. What would be an appropriate drug?

A.Metformin

B.Acarbose

C.Repaglinide

D.Insulin lispro

E.Pioglitazone

8.What is the drug of choice for management of adrenal glucocorticoidinduced osteoporosis?

A.Alendronate

B.Calcitonin

C.Estrogen

D.Ketoconazole

E.Vitamin D

9.Which drug has utility in inhibiting the severe secretory diarrhea of hormone-secreting tumors of the pancreas and GI tract, as well as in the treatment of acromegaly?

A.Octreotide

B.Leuprolide

C.Bromocriptine

D.Sertraline

E.Anastrazole

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