MCQs PHARMACOLOGY:Agents That Affect Bone Mineral Homeostasis

001. Action of the parathyroid hormone is:a) Increased calcium and phosphate absorption in intestine (by increased 1,25-dihydroxyvitamin D3 production) b) Decreased calcium excretion and increased phosphate excretion in kidneys c) In bone, calcium and phosphate resorption increased by high doses. Low doses may increase bone formation. d) All of the above
002. The parathyroid hormone increases serum calcium and decreases serum phosphate. This consideration is: a) True b) False.
003. The following statements about the parathyroid hormone are true, EXCEPT: a) The parathyroid hormone (PTH) is a single-chain peptide hormone composed of 84 amino acids b) The parathyroid hormone increases calcium and phosphate absorption in intestine (by increased 1,25- dihydroxyvitamin D3 production) c) The parathyroid hormone increases serum calcium and decreases serum phosphate d) The parathyroid hormone increases calcium excretion and decreases phosphate excretion in kidneys
004. Which of the following statements about calcitonin is true: a) Calcitonin secreted by parafollicular cells of the mammalian thyroid is a single-chain peptide hormone with 32 amino acids b) Effects of calcitonin are to lower serum calcium and phosphate by acting on bones and kidneys. c) Calcitonin inhibits osteoclastic bone resorption. d) All of the above
005. Mechanism of action of calcitonin is: a) Inhibits hydroxyapatite crystal formation, aggregation, and dissolution b) Raises intracellular cAMP in osteoclasts c) Activates bone resorption d) Inhibits macrophages
006. Indications for calcitonin administration are the following, EXCEPT: a) Hypercalcemia b) Paget's disease c) Hypophosphatemia d) Osteoporosis
007. Side effect of calcitonin is: a) Hypercalcemia b) Metastatic calcifications c) Tetany d) GI toxicity
008. Side effect of calcitonin is: a) Pruritus b) Hypotension c) Fractures d) Hypocalcemia
009. Glucocorticoid hormones alter bone mineral homeostasis: a) By antagonizing vitamin D-stimulated intestinal calcium transport b) By stimulating renal calcium excretion c) By increasing parathyroid hormone stimulated bone resorption d) By all of the above
010. Estrogens can prevent accelerated bone loss during the immediate postmenopausal period and at least transiently increase bone in the postmenopausal subject. This consideration is: a) True b) False
011. Action of vitamin D3 is: a) Increased calcium and phosphate absorption by 1,25-dihydroxyvitamin D3 b) Calcium and phosphate excretion may be decreased by 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 c) Increased calcium and phosphate resorption by 1,25-dihydroxyvitamin D3; bone formation may be increased by 25,24- dihydroxyvitamin D3 d) All of the above
012. Vitamin D3 increases serum calcium and phosphate. This consideration is: a) True b) False
013. Route of administration of vitamin D3 is: a) Subcutaneous b) Oral c) Intravenous d) Intranasal
014. Side effect of vitamin D3 is: a) Defective bone mineralization b) Metastatic calcifications c) Hepatic toxicity d) Nephrolithiasis
015. Indication of vitamin D3 is: a) Hypercalcemia b) Paget's disease c) Hypophosphatemia d) Osteomalacia
016. 25-hydroxyvitamin D3 (calcifediol) is less effective than 1,25-dihydroxyvitamin D3 (calcitriol) in stimulating intestinal calcium transport, so that hypercalcemia is less of a problem with calcifediol. This consideration is: a) True b) False
017. Route of administration of 25-hydroxyvitamin D3 (calcifediol) is: a) Oral b) Subcutaneous c) Intravenous d) Intranasal
018. Indication for 25-hydroxyvitamin D3 (calcifediol) administration is: a) Primary hyperparathyroidism b) Rickets c) Hypercalcemia d) Failure of vitamin D formation in skin
019. Side effect of 25-hydroxyvitamin D3 (calcifediol) is: a) Hypercalcemia b) Pruritus c) GI toxicity d) All of the above
020. Indications for 1,25-dihydroxyvitamin D3 (calcitriol) administration are the following, EXCEPT: a) Hypocalcemia in chronic renal failure b) Vitamin D-dependent rickets c) Malabsorption of vitamin D from intestine d) Elevated skeletal turnover
021. Indication for 1,25-dihydroxyvitamin D3 (calcitriol) administration is: a) Vitamin D resistance b) Elevated skeletal turnover c) Hypercalcemia of malignancy d) Hypophosphatemia
022. The following statement refers to 1,25-dihydroxyvitamin D3 (calcitriol): a) When rapidity of action is required, 1,25-dihydroxyvitamin D3 (calcitriol), 0.25-1 μg daily, is the vitamin D metabolite of choice, since it is capable of raising serum calcium within 24-48 hours b) Calcitriol also raises serum phosphate, though this action is usually not observed early in treatment c) Undergoes enterohepatic circulation d) All of the above
023. Which of the following statements refers to 1,25-dihydroxyvitamin D3 (calcitriol): a) The combined effect of calcitriol and all other vitamin D metabolites and analogs on both calcium and phosphate makes careful monitoring of the level of these minerals especially important to avoid ectopic calcification b) Does not undergo enterohepatic circulation c) Toxic to osteoclasts d) Bioavailability increases with the administered dose
024. Route of administration of 1,25-dihydroxyvitamin D3 (calcitriol) is: a) Subcutaneous b) Intravenous c) Intranasal d) Oral 025. Commercially available analogs of 1,25-dihydroxyvitamin D3 (calcitriol) are: a) Doxercalciferol (Hectoral) b) Paricalcitol (Zemplar) c) All of the above d) None of the above
026. Side effect of dihydrotachysterol is: a) Hepatic toxicity b) General malaise c) Lymphocytopenia d) Hypertension
027. Route of administration of dihydrotachysterol is: a) Intravenous b) Subcutaneous c) Oral d) Intranasal
028. Which of the following statements refers to cholecalciferol: a) Frequent monitoring of both calcium and phosphorus serum levels is necessary in case of intravenous administration b) Has potent anti-osteoclast activity – mechanism unknown c) Can usually lower serum calcium levels in 48 hours d) Mechanism of action: 1. Genomic effects 2. Cytoplasmic effects
029. Indication for cholecalciferol administration is: a) Hypercalcemia b) Parathyroid hormone deficiency c) Primary hyperparathyroidism d) Malabsorption of vitamin D from intestine
030. Route of administration of cholecalciferol is: a) Subcutaneous b) Intranasal c) Intravenous d) Oral
031. The unwanted effect of cholecalciferol is: a) Defective bone mineralization b) Lymphocytopenia c) CNS toxicity d) Metastatic calcifications
032. The unwanted effect of dihydrotachysterol is: a) Tetany b) Anorexia c) CNS toxicity d) Lymphocytopenia
033. Indication for dihydrotachysterol administration is: a) Parathyroid hormone resistance b) Paget's disease c) Increased osteolysis d) Hypophosphatemia
034. Conditions associated with hypophosphatemia include: a) Primary hyperparathyroidism b) Vitamin D deficiency c) Idiopathic hypercalciuria d) All of the above.
035. The long-term effects of hypophosphatemia include proximal muscle weakness and abnormal bone mineralization (osteomalacia). This consideration is: a) True b) False
036. Recommended phosphorus daily allowance is: a) 900-1200 mg b) 600-900 g c) 25 g d) 1.5-4 mg
037. Interactions with other drugs of phosphorus is: a) Amiloride: decrease renal excretion b) Glucocorticoids: decrease absorption c) Loop diuretics: increase renal excretion d) Calcitonin: increases renal excretion
38. Indication for pamidronate administration is: a) Failure of vitamin D formation in skin b) Hypoparathyroidism c) Elevated skeletal turnover d) Hypercalcemia
039. Route of administration of pamidronate is: a) Oral b) Subcutaneous c) Intranasal d) Intravenous
040. Correct statements about pamidronate include all of the following, EXCEPT: a) Because it causes gastric irritation, pamidronate is not available as an oral preparation b) Skeletal half-life is 24 h c) Fever and lymphocytopenia are reversible d) Can be irritable to the esophagus if not washed promptly to the stomach
041. Route of administration of alendronate is: a) Intravenous b) Subcutaneous c) Oral d) Intranasal
042. Correct statements about alendronate include all of the following, EXCEPT: a) Can be irritable to the esophagus if not washed promptly to the stomach b) 1st generation biphosphonate c) Reduces osteoclast activity without significantly affecting osteoblasts; useful in the treatment of Paget's disease d) More potent than EHDP; has a wider therapeutic window
043. Indications of alendronate are the following, EXCEPT: a) Hypoparathyroidism b) Glucocorticoid-induced osteoporosis c) Paget's disease d) Syndromes of ectopic calcification
044. Indication for etidronate administration is: a) Malabsorption of vitamin D from intestine b) Paget's disease c) Vitamin D deficiency in a diet d) Hypercalciuria
045. Indications for etidronate administration are the following, EXEPT: a) Paget's disease b) Osteoporosis c) Hypophosphatemia d) Hypercalcemia
046. Which of the following statements refers to etidronate: a) Reduces osteoclast activity without significantly affecting osteoblasts; useful in treatment of Paget's disease b) Serum phosphorus concentrations should be monitored at least daily in case of oral administration c) 2nd generation biphosphonate (amino-biphosphonate) d) Bioavailability increases with the administered dose
047. Correct statements about etidronate include all of the following, EXCEPT: a) Skeletal half-life is hundreds of days b) Bioavailability increases with the administered dose c) 2nd generation biphosphonate (amino-biphosphonate) d) 1st generation biphosphonate.
048. Unwanted effect of etidronate is: a) Anorexia b) Defective bone mineralization c) Hypercalcemia d) Cardiac arrhythmias
049. The major causes of hypocalcemia in the adult are: a) Hypoparathyroidism b) Vitamin D deficiency c) Renal failure and malabsorption d) All of the above
050. The major causes of hypercalcemia in the adult are the following, EXCEPT
a) Hyperparathyroidism b) Cancer with or without bone metastases c) Renal failure and malabsorption d) Hypervitaminosis D
051. Which of the following statements refers to calcium: a) Recommended Ca daily allowance for males: 1. 1-10 years: 800 mg 2. 11-18 years: 1200 mg 3. 19-50 years: 1000 mg 4. > 51 years: 1000 mg b) Ca chloride is very irritating and can cause necrosis if extravasated c) In achlorhydric patients calcium carbonate should be given with meals to increase absorption or patient switched to calcium citrate, which is somewhat better absorbed d) All of the above
052. Indication for calcium administration is: a) Failure of formation of vitamin D in skin b) Malabsorption of vitamin D from intestine c) Hypercalcemia of malignancy d) Vitamin D deficiency
053. Which of the calcium preparations is the most preferable for IV injection a) Calcium gluceptate (0.9 meq calcium/mL) b) Calcium gluconate (0.45 meq calcium/mL) c) Calcium chloride (0.68-1.36 meq calcium/mL) d) All of the above
054. Which of the oral calcium preparations is often the preparation of choice: a) Calcium carbonate (40% calcium) b) Calcium lactate (13% calcium) c) Calcium phosphate (25% calcium) d) Calcium citrate (17% calcium)
055. Interactions with other drugs of calcium is: a) Ethanol: decreases absorption b) Loop diuretics: increase renal excretion c) Glucocorticoids: stimulate renal excretion d) All of the above
056. Correct statements about magnesium include all of the following, EXCEPT: a) Magnesium is mainly an intracellular cation, and is the fourth most abundant cation in the body b) The recommended dietary amounts of magnesium have been set at 6 mg/kg day (350-400 mg) c) The most common specific causes encountered in clinical practice are: diet, alcoholism (drinking), diarrhea and malabsorption, diabetes mellitus, diuretics, and drugs such as aminoglycosides and amphotericin d) It is a physiological calcium agonist
057. Recommended magnesium daily allowance is: a) 350-400 mg b) 6-9 g c) 25 g d) 1.5-4 mg
058. The major causes of hypomagnesaemia are: a) Insufficient dietary intake, e.g. malnutrition b) Abnormal gastrointestinal loss, e.g. severe diarrhea or chronic alcoholism c) Abnormal renal loss, e.g. diabetes mellitus or during therapy with some kind of drugs such as amphotericin B, gentamicin, cisplatin, cardiac glycosides, distal and loop diuretics d) All of the above
059. Which of the magnesium preparation is the most preferable for I.V. injection a) Magnesium sulfate b) Magnesium chloride c) Magnesium glutamate d) All of the above
060. Which of the oral magnesium preparations is often the preparation of choice: a) Magnesium lactate b) Magnesium oxide c) MagneB6 (Mg pidolate / Mg lactate + pyridoxine hydrochloride) d) All of the above.
061. Correct statements about fluoride include all of the following, EXCEPT: a) Fluoride is effective for the prophylaxis of dental caries b) Fluoride is accumulated by bone and teeth, where it may stabilize the hydroxyapatite crystalc) Subjects living in areas with naturally fluoridated water (1-2 ppm) had more dental caries and fewer vertebral compression fractures than subjects living in nonfluoridated water areas d) Chronic exposure to very high level of fluoride dust in the inspired air results in crippling fluorosis, characterized by thickening of the cortex of long bones and bony exostoses.
062. Recommended fluoride daily allowance is: a) 1.5-4 mg b) 600-900 g c) 25 g d) 350-400 mg
063. Which of the following statements refers to gallium nitrate: a) It is approved by the FDA for the management of hypercalcemia of malignancy b) This drug acts by inhibiting bone resorption c) Because of potential nephrotoxicity, patients should be well-hydrated and have good renal output before starting the infusion d) All of the above
064. Which of the following statements refers to plicamycin (formerly mithramycin): a) Duration of action is usually several days b) Mechanism of cytotoxic action appears to involve its binding to DNA, possibly through an antibiotic-Mg2+ complex. c) The drug causes plasma calcium levels to decrease, apparently through an action on osteoclasts that is independent of its action on tumor cells and useful in hypercalcemia. d) All of the above.
065. Unwanted effects of plicamycin (formerly mithramycin) are the following, EXEPT: a) Thrombocytopenia b) GI toxicity c) Bleeding disorders d) Fractures
066. Unwanted effect of plicamycin (formerly mithramycin) is: a) Diarrhea b) Myelosuppression c) Nephrolithiasis d) Metastatic calcifications
067. Indication for plicamycin (formerly mithramycin) administration is: a) Testicular cancers refractory to standard treatment b) Paget’s disease c) Hypercalcemia of malignancy d) All of the above
068. Route of administration of plicamycin is: a) Intravenous b) Subcutaneous c) Intranasal d) Oral