CDN Pharmacology & Drug-Nutrient Interactions 3

Question 1

Long-term use of combined oral contraceptives is most commonly associated with depletion of which nutrient, with implications for women planning pregnancy?

Accepted Answer

Folate

Answer

Oral contraceptives increase folate metabolism and urinary excretion; adequate folate status is critical before conception to prevent neural tube defects.

Question 2

Chronic alcohol abuse impairs the activation of which vitamin primarily through its effects on hepatic hydroxylation?

Accepted Answer

Vitamin D

Answer

Alcohol impairs the liver's ability to perform 25-hydroxylation of vitamin D, the first essential step in producing the active hormonal form, leading to metabolic bone disease.

Question 3

Long-term use of aluminum-containing antacids can deplete which mineral by forming insoluble complexes in the gastrointestinal tract?

Accepted Answer

Phosphate

Answer

Aluminum hydroxide binds dietary phosphate in the gut forming insoluble aluminum phosphate, reducing phosphate absorption and potentially causing hypophosphatemia.

Question 4

The antibiotic trimethoprim reduces availability of which nutrient by competitively inhibiting the enzyme dihydrofolate reductase?

Accepted Answer

Folate

Answer

Trimethoprim inhibits dihydrofolate reductase, the enzyme required to convert dietary folate into its active tetrahydrofolate form needed for DNA synthesis.

Question 5

Cyclosporine, an immunosuppressant used after organ transplantation, causes wasting of which electrolyte through nephrotoxic effects on the renal tubules?

Accepted Answer

Magnesium

Answer

Cyclosporine causes renal tubular dysfunction that impairs magnesium reabsorption, leading to hypomagnesemia which can manifest as muscle cramps, tremors, and cardiac arrhythmias.

(CDN) Certified Dietician Nutritionist Practice Test

(CDN) Certified Dietician Nutritionist Practice Test

CDN Pharmacology & Drug-Nutrient Interactions 3