Vitamins/minerals Flashcards
examples of patients who have a true need for MVIs
inadequate dietary intake, increased metabolic requirements, poor absorption, and iatrogenic situations
inadequate dietary intake patients
alcoholics, impoverished, those who have eating disorders, or on trendy diet
increased metabolic requirements patients
pregnant and breast feeding women, infants/children, post-surgical, cancer, or trauma patients
poor absorption patients
elderly, patients with GI disorders (diarrhea, constipation, IBS), celiac disease, gastric bypass
iatrogenic situation patients
taking prolonged ABX, those with drug-nutrient interactions, those receiving parenteral nutrition
deficiencies of fat soluble vitamins occur when
fat intake is limited or fat absorption is compromised
diseases that affect fat absorption
celiac disease, cystic fibrosis, jaundice, cirrhosis, short bowel syndrome
drugs that affect fat absorption
cholestyramine, orlistat, mineral oil
function of vitamin A
eyes, analogues for cancers, skin disorders such as acne
s/sx of vitamin A deficiency
night blindness, dry eyes, dry skin, poor bone growth
safety concerns of excess vitamin A
teratogenic effects at doses > 3000 IU
chronic daily ingestion of > 5000 IU results in toxicity
should not exceed 10,000 IU
functions of vitamin D
bone formation and calcium regulation
three forms of vitamin D
- cholecalciferol
- ergocalciferol
- calcitrol
when skin is exposed to sunlight UV radiation what happens to vitamin D
becomes cholecalciferol
what is cholecalciferol converted into
converted by the liver into 25-hydroxycholecalciferol
25-hydroxycholecalciferol is hydroxylated by the kidney into
its active form, 1-25 dihydroxycholecalciferol
what does 1-25 dihydroxycholecalciferol do
regulates calcium
causes of vitamin D deficiency
chronic renal failure, inadequate sun exposure, and chronic phenytoin use
s/sx of vitamin D deficiency
osteoporosis, rickets, and muscle weakness
dose of vitamin D for osteoporosis prevention for age 18-70 yo
400-600 IU/day
dose of vitamin D for osteoporosis prevention for age > 70 yo
600-800 IU/day
dose of vitamin D for osteoporosis treatment for age < 50 yo
400-800 IU/day
dose of vitamin D for osteoporosis treatment for age > 50 yo
800-1000 IU/day
dietary supplementation of vitamin D should not exceed
2000 IU/day
problems related to elevated calcium
hypercalcemia (N/V, constipation, anorexia, polyuria), kidney stones, renal failure, soft tissue calcification
what drugs decrease levels of vitamin D
phenytoin, carbamazepine, barbiturates
function of vitamin E
antioxidant that protects cell membranes from free radicals
high doses of vitamin E decreases
decreased vitamin K production –> warfarin anticoagulation –> increased risk of bleeding
functions of vitamin K
bone mineralization and required for normal coagulation (production and activation of clotting factors)
causes of vitamin K deficiency
malabsorption, bowel resections, and liver disorders
possible reduced gut bacteria due to antibiotic
s/sx of vitamin K deficiency
increased bruising and bleeding (increased PT and INR)
vitamin K doses for males > or equal to 19 yo
120 mcg/day
vitamin K doses for females > or equal to 19 yo
90 mcg/day
vitamin K supplementation interactions
warfarin (INR changes) –> inhibits warfarin ability to anticoagulate
functions of vitamin C
antioxidant and helps increase iron absorption
dosing of vitamin C should not exceed more than
1500mg of one time
doses of ________ vitamin C a day are not recommended
greater than or equal to 4 g/day (associated with greater ade)
excess vitamin C can cause
nausea, diarrhea, stomach cramps, and kidney stones
vitamin b12
cyanocobalamin
functions of b12
myelin formation in CNS and folate methylation and metabolism
foods vitamin b12 my be found in
eggs, meat, poultry, milk
causes of b12 deficiency
cancer, alcoholism, long-term metformin use, vegetarian or vegan diets, long-term PPI use
s/sx of vitamin b12 deficiency
macrocytic anemia, peripheral neuropathy, diarrhea, irritability, forgetfulness
vitamin b9
folic acid
functions of b9
dna synthesis, rbc maturation; CHO, fat and protein metabolism
causes of b9 deficiency
b12 deficiency, alcoholism, liver disease, DHFR inhibitors, anticonvulsants
vitamin b6
pyridoxine
functions of b6
cofactor for > 60 enzymes and involved in heme production
causes of b6 deficiency
alcoholism, sever diarrhea, isoniazid
s/sx of b6 deficiency
pellagra-like, peripheral neuropathy
vitamin b2
riboflavin
functions of b2
hair, skin, nail integrity/growth, vision
causes of b2 deficiency
alcoholism and early pregnancy
s/sx of b2 deficiency
blurry vision
excess b2
bright yellow urine discoloration
functions of calcium
bone and teeth health, nerve signaling pathway, muscle contractions, and other intracellular processes
causes of calcium deficiency
malabsorption, hypoparathyroidism, vitamin D deficiency, renal deficiency, long-term anticonvulsants, postmenopausal women, patients with lactose intolerance
s/sx of calcium deficiency
convulsions, tetany, behavioral and personality disorders, mental and growth retardation, and bone deformities, spontaneous fractures
female calcium doses
18-50 yo
1000 mg/day
female calcium doses
> 51 yo
1200 mg/day
male calcium doses
18-70 yo
1000 mg/day
male calcium doses
> 70 yo
1200 mg/day
how much elemental calcium does calcium carbonate have
40% elemental calcium
calcium carbonate product examples
caltrate, tums, rolaids
counseling for calcium carbonate
requires acid in stomach for absorption, must take with a meal
calcium carbonate is not a good choice for patients on..
PPIs, H2RAs, older patients
how much elemental calcium does calcium citrate have
21% elemental calcium
counseling for calcium citrate
bioavailability better, so does not need to be taken with food
common adverse effects of calcium supplements
gas and constipation
DDI with calcium supplements
quinolone antibiotics, tetracycline, levothyroxine, zinc, and iron
excessive calcium can cause
renal insufficiency, hyperparathyroidism, and kidney stones
possible risk of CV disease, heart attack and stroke
drugs that increase risk of hypercalcemia
thiazide diuretics
function of iron
plays an important role in oxygen and electron transport
two forms of dietary iron
heme and nonheme
heme iron found in
meats and is reasonably well absorbed
non heme iron is found in
enriched grains and dark green veggies and is poorly absorbed
causes of iron deficiency
poor nutrition, malabsorption, pregnancy/lactation, and blood loss (menstruation, PUD, esophageal varices, cancer, surgery, or traumatic injury)
s/sx of iron deficiency
microcytic anemia, split or spoon shaped fingernails, pica
elemental iron in ferrous fumarate
33% elemental iron
elemental iron in ferrous sulfate
20% elemental iron
elemental iron in ferrous gluconate
12% elemental iron
adverse side effects of iron supplements
nausea, abdominal pain (try to take on empty stomach if tolerated), and constipation dark tarry stools
DDI with iron supplements
quinolones, tetracyclines, levothyroxine, zinc and calcium
excess iron side effects
vomiting, diarrhea, abdominal pain, electrolyte imbalances, shock, CV collapse
