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Flashcards in Common Vitamins and Minerals Deck (41)

What are the different types of calcium supplements available? How much elemental calcium do they contain?

Calcium carbonate has 40%
Calcium citrate has 21%
Calcium lactate has 18%
Calcium gluconate has 9%


How much calcium should a person take?

For optimal absorption, calcium doses should not exceed 500mg of elemental calcium
If a higher amount of calcium supplement is needed, should be divided throughout the day (BID to TID dosing)


Describe calcium carbonate

Best calcium absorption occurs in an acidic environment, and therefore should be taken with meals
Cheapest option
Often first line
Well tolerate
Major side effect: constipation


Describe calcium citrate

Increased absorption compared to calcium carbonate, especially in patients with a high gastric pH
Recommended for patients on proton pump inhibitors or H2 blockers, inflammatory bowel disease or absorption disorders (e.g., bariatric patients)
May be taken on an empty stomach
Have less elemental calcium versus carbonate, therefore more doses may be required


Do calcium supplements contain lead?

Natural preparations from oyster shells or bone meal may contain some lead, but not likely an issue as calcium blocks lead absorption


Do calcium supplements contain magnesium?

Some calcium supplements may also contain magnesium for potential laxative effect


What happens if a person takes too much calcium?

Excess ingestion of calcium potentially may cause kidney stones, milk-alkali syndrome or renal insufficiency


What schedule are iron supplements?

Preparations containing more than 30 mg of elemental iron are schedule II
Death and accidental poisoning has occurred in children who ingested small amounts (200 mg)


In what form are iron supplements?

All dietary iron must be reduced to ferrous form (therefore ferrous iron is absorbed more readily than ferric form)


Where does absorption of iron occur?

Most of iron absorption occurs in the distal duodenum and proximal jejunum


Are enteric-coated or sustained-release iron supplements good options?

No, because iron is release further down the intestinal tract and not absorbed


Should everyone take iron supplements?

Iron supplementation should only occur under the advice of a health care provider when there is known or suspected iron deficiency or an increased need for iron


Why is excess iron bad?

Excess iron is stored in tissues and organs, which may lead to cirrhosis and/or heart failure


What are the classic formulations of iron available?

Ferrous gluconate (12% elemental iron)
Ferrous sulfate (20% elemental iron)
Ferrous fumarate (33% elemental iron)


What are the newer formulations of iron available?

Heme-iron polypeptide (Proferrin; hemoglobin from bovine red blood cells)
Polysaccharide iron complex (Triferexx, FeraMAX 150; ferric iron complex with hydrolyzed starch, unproven claim that i causes less GI irritation)


How should iron be taken? Why?

Iron salts should be taken on an empty stomach
Foods such as cereals, dietary fibres, tea, coffee, eggs and milk may impair absorption
If stomach irritation occurs, may be administered with food
Suggest to start with low doses, then gradual increase to recommended dose


What are the different drug interactions of iron?

Antacids, proton pump inhibitors, calcium supplements and antibiotics (quinolones, tetracyclines)


What are the side effects of iron?

GI side effects: abdominal discomfort, nausea/vomiting, diarrhea/constipation (likely directly related to the amount of elemental iron)


Do B vitamins help relieve stress and increase energy?

High amounts of B vitamins are found in energy drinks and supplements
B vitamins are helpful to release energy from foods
Our diet supplies all required B vitamins and extra is excreted in the urine


If someone is looking for B vitamins to relieve stress, what is suggested instead?

Reducing caffeine, alcohol and smoking
Sufficient sleep
Relaxation techniques (guided imagery, meditation)


Will B vitamins reduce the risk of skin cancer?

Recent ONTRAC Study found that niacinamide may help high-risk patients who already have non-melanoma skin cancer
In the study, they found a decreased risk of skin cancer by 23%
Benefit was not demonstrated in patients without skin cancer
Not a replacement for current recommendations for sun protection


What is AMD?

Age-related macular degeneration
Leading cause of poor vision in people over 60 years old and of adult blindness
Loss of central vision, yet peripheral vision is unaffected


What causes AMD?

Results from the deterioration of the macula
Macula is a small are at the centre of the retina in the back of the eye, purpose is to permit seeing fine details clearly


What are the symptoms of AMD?

Decrease in sharp, straight ahead vision need for driving,reading, recognizing faces and looking at detail


What causes AMD?

Specific cause is unknown


What are the two types of AMD?

Dry (atrophic) AMD
Wet (neovascular) AMD


Describe dry AMD

Result from thinning of the macula
More common form of AMD (90%)
Development occurs over many years, leading to gradual vision loss
There are 3 stages: early, intermediate and advanced


Describe wet AMD

Results from abnormal blood vessels growing under the retina
Less common but more serious
Quickly progresses, leading to severe vision loss or blindness


What are the treatments for wet AMD?

Anti-vascular endothelial growth factor (anti-VEGF) injections
Photodynamic therapy


What is the treatment for dry AMD?

No proven effective treatment
Found that a unique high dose antioxidant vitamins and zinc lowered the progression risk to advanced stage (and further vision loss)


What is the original formula for dry AMD?

High doses of vitamin A, vitamin C and beta-carotene as well as zinc
Beta-caroten is associated with an increased risk of lung cancer, especially in smokers (past or current)


What is the AREDS2 formula?

New formulatino without beta-carotene, added lutein and zeaxanthin
Found to be equally as effective


What is recommended by HCPs for those at high risk for advanced form of AMD?

For this at risk for intermediate dry AMD in both eyes or advanced ADM in only one eye, the original formula for non-smokers only, or the AREDS2 formula


Is treatment for dry AMD recommended for everyone?

No. Not for early dry AMD or for wet AMD


What are some drugs that can cause drug-induced nutrient depletion?



How does orlistat induce nutrient depletion?

Based on the pharmacologic action, there may be a decrease in the levels of some fat soluble vitamins (A, D, E, K) and beta-carotene
Recommended for patients to take a multivitamin supplement
Separate supplement from orlistat dose by a minimum of 2 hours


How does metformin induce nutrient depletion?

Antidiabetic medication
May lead to decrease in folate (B9) and vitamin B12 in some patients
Monitor hematological parameters yearly
Monitor vitamin B12 and homocysteine levels yearly
Supplements may be required in some patients


How do corticosteroids induce nutrient depletion?

Oral corticosteroids with high mineralocorticoid activity (e.g., hydrocortisone, cortisone, prednisone, prednisolone) can cause steroid induced osteoporosis
Supplements with calcium and vitamin D are needed in patients taking over 7.5 mg of prednisone daily (or equivalent)
Long term treatment needs monitoring every 6 months of bone mineral density and calcium levels


What are some drug supplement interactions?

Vitamin A, beta-carotene
Vitamin E


What do vitamin A and beta-carotene interact with?

Avoid combination with retinoids (isotrentinoin, acitretin, etretinate, tazarotene) because it leads to additive toxic effects
Avoid combination with hepatotoxic medications (e.g., acetaminophen, carbamazepine, methotrexate), as it may increase risk of liver disease
Avoid combination with warfarin due to increased risk of vitamin A toxicity and bleeding


What does vitamin E interact with?

When combined with warfarin, ASA or NSAIDs may increased risk of bleeding
Management: restrict vitamin E dose of 200 IU or less per day and monitor INR (if on warfarin)