Vitamin Supplementation Flashcards
Magnesium
- Forms
NOT Citrate and Hydroxide, those are used for constipation
Use Magnesium:
- Asparate
- Carbonate
- Gluconate
Magnesium
- Indication
Supplementation only used in those deficient
Causes of deficiency:
- Malnutrition (alcohol use disorder)
- Chronic diarrhea
- IBD
- Diuretics
- Critically ill
Magnesium
- Sign and Symptoms
No clear tell tale signs of magnesium deficiency
Magnesium
- Indications with Conflicting evidence
Cardiovascular
Diabetes
Muscles
Bone health
Headaches
Diabetes
Magnesium
- Adverse Effects
- Diarrhea
- Nausea/Abdominal Cramps
Toxicity:
- Hypotension
- Facial flushing
- Muscle weakness
- Arrhythmia
- Cardiac arrest
Magnesium
- Drug Interactions
Impairs absorption of:
- Antibiotics
- Bisphosphonates
Vitamin D
- Forms
D2 (Supplementation): Plants and Fungi
D3 (Supplementation): Synthesized in Skin, Fatty fish and egg yolks
D (Calcitriol - Rx)
- Mainly used in CKD
Vitamin D
- Measuring Levels
Measure 25-hydroxyvitamin D
- Routine vitamin D not recommended, not even required before or after supplementation (Expensive)
Vitamin D
- High Risk Patients
Measuring is indicated in high risk patients with:
- Malabsorption syndromes
- Significant liver disease
- CKD
- Unexplained bone pain
- Unusual fractures
- Other evidence of metabolic bone disease
Vitamin D
- Levels
25-hydroxyvitamin D
< 30 nmol/L = Risk of Vitamin D deficiency
30-50 nmol/L = Clinical features of inadequacy
> 50 nmol/L = Adequate bone health
> 125 nmol/L = Potential for A/E
> 250 nmol/L = Toxicity
Vitamin D
- Sources
Food Sources
- Egg yolks
- Fatty fish
- Fortified foods (Has vitamin D added in)
Exposure to UVB sunlight (expose arms and legs to sunlight for 10-15 mins in summer months)
- Caution: can increase cancer risk
- NO tanning beds
Vitamin D
- Synthesis
D3: UVB on skin, Skin processes it into D3
D2 and D3: Comes from diet and enters circulation
D2 and D3 converted by liver into Calcidiol which is then converted in kidneys to Calcitriol
Vitamin D
- Supplementation
Children and Adults 9-70 years
- RDA 600 IU
- TUL 4000 IU
Adults older than 70 years
- RDA 800 IU
- TUL 4000 IU
Vitamin D
- Recommended Dose
RDA of 600-800 IU
- Reasonable to advise year round supplementation
- Not recommended to exceed RDA
Vitamin D
- High Dose/ once year recommendation
No recommendation
- Increases risk of fractures
Vitamin D
- D2 vs D3
D3 is recommended over D2 as it is shown to be 3x more effective than D2 at increasing 25-hydroxyvitamin D levels
Vitamin D
- Decreased metabolism of Vit D (High Dose)
First Week:
- 5000 U daily or 50,000 weekly
Maintenance:
- 1500-2000 U daily
Vitamin D
- Vitamin D Resistant Rickets (High Dose)
12,000 - 500,000 U daily
Vitamin D
- Hypoparathyroidism (High Dose)
50,000 - 200,000 daily
Vitamin D
- Toxicity
Greater than 250 nm can cause Hypercalcemia:
Neurological Effects:
- Confusion
- Depression
- Psychosis
GI Effects
- Vomiting
- Abdominal Pain
- Anorexia
- Constipation
Hypertension, Arrhythmias
Hypercalcirua
Vitamin D
- Indications with Conflicting Evidence
- Cancer prevention
- Cardiovascular disease
- Autoimmune disorders
- Dementia
Vitamin B12
- Signs and Symptoms
- Fatigue
- Weakness
- Pallor
Neurological Symptoms (Can be irreversible if not treated)
- Numbness
- Tingling
- Cognitive Impairment
- Depression
Vitamin B12
- Risk Factors (Diet and Lifestyle)
Vegan Diet
Chronic Excessive Alcohol Use
Vitamin B12
- Risk Factors (Medical History)
- Age
- Gastrointestinal Surgery
- Pernicious Anemia
- Crohn’s
- Celiac
Vitamin B12
- RIsk Factors (Medications)
- Metformin
- PPIs
- H2 Receptor Antagonists
Vitamin B12
- Measuring Levels
Routine testing not recommended
- Normal Range: 150-220 pmol/L
Test if patient has symptoms of B12 deficiency
Vitamin B12
- Management (Initial Investigation)
Patient has either risk factor / specific symptoms (cognitive impairment, peripheral neuropathy) / non-specific symptoms (fatigue, depression)
- Check B12 levels
Vitamin B12
- Management (Deficiency Levels)
B12 < 75 pmol/L = High Probability of Deficiency
B12 75-150 pmol/L = Possible B12 deficiency
B12 > 150 pmol/L = Low Probability of Symptomatic Deficiency
Vitamin B12 Management
General:
- Address underlying cause
- Implement dietary changes
Relatively Low:
- B12 supplements for 2 months
- Assess for clinical improvements and retest levels
Deficient:
- B12 supplements
- Investigate for pernicious anemia or malabsorption
Vitamin B12 - Treatment Recommendations
- Adults with normal absorption
Oral: 1000 mcg daily
Vitamin B12 - Treatment Recommendations
- Adults with Impaired Absorption
Very High Dose if intrinsic factor not required for absorption, can you passive diffusion
- Oral: 1000-2000 mcg daily
Vitamin B12 - Treatment Recommendations
- Adults with dietary deficiency
Oral: 500-2000 mcg daily
Vitamin B12 - Treatment Recommendations
- Pernicious Anemia
IM/Deep SC:
- 1000 mcg once per week x 4 weeks, then once per month
High Dose Oral:
- 1000-2000 mcg daily if no acute symptoms of anemia of neurological complications
Vitamin B12 - Treatment Recommendations
- Altered GI Anatomy
IM/Deep SC:
- 1000 mcg once per week x 4 weeks, then once per month
Vitamin B12 - Treatment Recommendations
- Adults anemia or neurologic symptoms or pregnancy
IM/Deep SC:
- 1000 mcg daily or every other day for 1-2 weeks, then once per month
Oral:
- Once corrected, may trial oral 1000-2000 mcg based on patient preference and adequate B12 levels
Vitamin B12
- Monitoring
Hematological parameters;
- Should resolve within weeks
Neurological parameters
- Should resolve within months
Check B12 levels every 3-6 months
Celiac Disease
- Deficient Nutrients
- Folate
- B12
- Fat-Soluble Vitamins
- Calcium
- Iron
Crohn’s
- Deficient Nutrients
- Iron
- B12
- Fat-Soluble Vitamins
- Zinc
Short Bowel Syndrome
- Deficient Nutrients
- Iron
- B12
- Fat-Soluble Vitamins
- Calcium
- Iron
- Zinc
Chronic Pancreatitis
- Deficient Nutrients
- B12
- Fat Soluble Vitamins
- Calcium
Alcohol Use Disorder
- Deficient Nutrients
Thiamine Deficiency
- Increases risk of Wernicke-Korsakoff Syndrome and Beriberi Disease
Wernicke-Korsakoff Syndrome
- What is it
Wernicke Encephalopathy
- Confusion, Ataxia (difficulty walking), Nystagmus
- Reversible by Thiamine supplementation
Korsakoff Psychosis
- Severe memory impairment, hallucinations
- Chronic, irreversible
Wernicke-Korsakoff Syndrome
- Treatment
Initial:
- 250-500 mg IM/IV tid for 2-7 days
- Then 250 mg qd for 3-5 days
Maintenance:
- 100 mg daily
Prevention:
- 100-200 mg IM/IM qd for 3-5 days
Beriberi
- What is it
Wet Beriberi (High Output Cardiac Failure)
- Palpitations, weakness, shortness of breath
Dry Beriberi
- Progressive weakness and muscle atrophy
- Peripheral neuropathy
- Absent knee jerk
Beriberi
- Treatment
Initial:
- 100-200mg IM,IV,PO tid for 2-3 days
Maintenance
- 5-100mg qd until no longer deficient
Vitamins
- Cancer
Not much evidence for cancer prevention
- Avoid Vitamin E (Smokers, and Men over 60 years old = Increases cancer risk)
- Avoid Vitamin B (Breast cancer)
- Avoid Beta-Carotene (Gastric and Lung Cancer)
Vitamins
- Cardiovascular Primary Prevention
Little evidence for
- Vitamin C, D
- Omega-3-fatty-acids
Vitamins
- CVD Secondary Prevention
Avoid routine use of antioxidants
- Beta-carotene, Vitamin E, Selenium
Omega-3 Fatty acids have unlikely benefits but minimal risks
- High dose icosapent ethyl is used to reduce elevated triglycerides
Vitamins
- Cognitive Decline
Antioxidants, Multivitamins
- No benefits
B Vitamins
- No benefits
Vitamins
- Type 2 Diabetes Prevention
B Vitamins
- B6, B12, Folic acid did not slow progression of diabetic nephropathy
Vitamin D
- Is not standard but had potential in slowing progression of diabetes
THe two types of Drug-Nutrient Interactions
Pharmacodynamic (Drug action)
Pharmacokinetic (ADME)
Absorption Interactions
- Mechanisms
- Chelation (Drug nutrient binding)
- pH changes affecting solubility
- Alterations in GI motility / enzyme activity
Absorption Interactions
- Examples
Calcium, Iron, Zinc, Magnesium
- Can bind to tetracyclines and fluoroquinolones to reduce absorption
Antacids (Calcium Carbonate, Aluminium Hydroxide)
- Reduces absorption of iron and B12 due to increased gastric pH
Metabolism Interactions
- Mechanisms
Enzyme inhibition or induction
- Cytochrome P450
Nutrients affecting drug absorption
Metabolism Interactions
- Examples
Vitamin K + Warfarin = Reduced effectiveness of warfarin
Grapefruit Juice - Inhibits CYP3A4
- Increases concentrations of some statins and calcium channel blockers
Distribution Interactions
- Mechanism
Competition between drugs and nutrients for plasma protein binding sites
Distribution Interactions
- Example
Vitamin A and Warfarin
- Vitamin A can displace warfarin from protein binding = Increased bleeding risk
Excretion Interactions
- Mechanism
Drugs that affect renal excretion of nutrients
Nutrients that modify drug clearance
Excretion Interactions
- Examples
Loop Diuretics
- Increases excretion of potassium, magnesium, calcium
Lithium
- Sodium intake affects lithium excretion = Increased clearance
Nutrient Deficiencies induced by drugs
- Vitamin B12
PPI
Metformin
Nutrient Deficiencies induced by drugs
- Folic Acid
Methotrexate
Phenytoin
Nutrient Deficiencies induced by drugs
- Calcium
Corticosteroids
Nutrient Deficiencies induced by drugs
- Vitamin D
Corticosteroids
Nutrients affecting drug efficacy
- Iron
Reduces efficacy of levothyroxine
Nutrients affecting drug efficacy
- Calcium
Reduces efficacy of levothyroxine
Nutrients affecting drug efficacy
- High Protein Diet
Reduces efficacy of levodopa
- Increases competition for transport across BBB
