Drug-nutrient-interactions

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Transcript Drug-nutrient-interactions

EU Legislation
Jane McClenaghan BscHons, DipION
Nutritional Therapist
Are you aware…?
1. Food Supplements Directive
2. Traditional Herbal Medicines Products Directive
3. Nutritional and Health Claims Regulation
ROI Medicines Act
Any nutrient above 1 times the RDA is a medicine
RDA’s
Vitamins
Vitamin A
800 μg
Vitamin D
5 μg
Vitamin E
10 mg
Vitamin C
60 mg
Thiamin
1.4 mg
Riboflavin
1.6 mg
Niacin
18 mg
Vitamin B6
2 mg
Folic acid
200 μg
Vitamin B12
1 μg
Biotin
0.15 mg
Pantothenic acid 6 mg
Minerals
Calcium
800 mg
Phosphorus
800 mg
Iron
14 mg
Magnesium
300 mg
Zinc
15 mg
Iodine
150 μg
Food Supplements Directive
First proposed in 1988
Aims of the Directive
1.
2.
3.
4.
5.
6.
7.
Recognition of the existence of food supplements
Harmonisation of legislation across the community
Recognition that not all groups achieve nutritional
goals through diet
Recognition that some consumers choose to
supplement their diet for lifestyle or other reasons
To ensure consumer protection through safety and
labelling criteria
To define food supplements
To define conformance criteria
Aims of the Directive
8. To establish a positive list of vitamins and minerals
that may be used in food supplements
9. Recognition of scientific and technological innovation
10. Recognition that excessive vitamin/mineral intake
may cause adverse effects so that maximum levels of
intake need to be set
11. Recognition that supplement levels should be
significant
12. A requirement on government to provide efficient
monitoring
The creation of Positive Lists
Within 5 [from 2003] years the
Commission shall submit to the
European Parliament and the Council a
report on the advisability of establishing
specific rules, including, where
appropriate, positive lists, on categories
of nutrients or of other substances with
a nutritional or physiological effect.
Draft Maximum Permitted Levels
Due to be published end April 2009
… may not be published for another year
…implementation may be 2-3 years away
The Maximum Permitted Level
Debate
1. nutrients for which there is no risk of over
consumption (eg: some B group vitamins)
2. nutrients for which there is a low risk of over
consumption (eg vitamin C, magnesium)
3. nutrients for which there is a risk of excessive
intake (eg Vitamin A, Folic acid, iron)
The Maximum Permitted Level
Debate
nutrients for which there is no risk of over
consumption
Option 1: No numerical maximum amounts
established.
Option 2: Numerical maximum amounts (not based
on safety)
The Maximum Permitted Level
Debate
nutrients for which there is a low risk of over
consumption
Option 1: Numerical maximum amounts
Option 2: Numerical maximum amounts with advisory
statements.
The Maximum Permitted Level
Debate
nutrients for which there is a risk of excessive intake
Option 1: Numerical maximum amounts.
Option 2: Numerical maximum amounts with
restrictions.
Nutrition Claims
Claims which state, suggest or imply that
a food has particular beneficial
nutritional properties due to:
• The energy value it provides, provides
at a reduced or increased rate, or does
not provide
• The nutrients or other substances it
contains, contains in reduced or
increased proportions, or does not
contain
Health Claims
Claims which state, suggest or imply that
a relationship exists between a food
category,
• a food or one of its constituents and
health.
• Only ‘approved’ health claims may be
made.
Health claims not permitted
• Claims which suggest that health can be affected by
not consuming the food
• Claims which make reference to the rate or amount
of weight loss
• Claims which make reference to recommendations by
individual doctors or health professionals and
associations other than national associations of
medical, nutrition or dietetic professionals and healthrelated charities (national rules of individual member
states apply to recommendations or endorsement by
such associations and charities).
Traditional Herbal Medicinal
Products Directive
To provide a special, simplified registration
procedure for certain traditional medicinal
products without having to prove efficacy
Requirements of THMPD
• Safety (published bibliographical)
• Quality (pharmaceutical GMP)
• Tradition
30 years demonstrated use
15 years use in E.U.
Drug-Nutrient Interactions
Jane McClenaghan BscHons, DipION
Nutritional Therapist
‘Killer Grapefruit alert to Slimmers’
The Sun, 3 April 2009
How drugs & nutrients interact…
1. Depletions
-
interference with nutrient absorption
interference with metabolic pathways
depletion of nutrients
2. Adverse reaction of drug + nutrient/food/drink
- Absorption of drug
- Bioavailability (increase or decrease) of
drug
- Inhibit/modify action of drug
How drugs & nutrients interact…
3. Reduction of drug side effects
4. Risk of overdose
- Enhanced bioavailability
- Enhanced drug action
5.Prevent drug action
Where supplementation may be
beneficial…
 if drug causes
depletion/interference of nutrient
 reduction or prevention of sideeffects
 supportive interaction
Avoid if..
×
×
Adverse reaction
Reduced drug absorption or
bioavailability
General Cautions…
Betaine HCl
Licorice
Psyllium
Valerian
Acne drugs
Antacids
Aspirin
NSAIDs
Blood pressure meds
(use deglycyrrhised)
May delay absorption
Leave 2 hours
Drowsiness with sedatives
With vit A may cause high
blood levels vit A
Decrease folic acid
absorption
Be Aware...
Vitamin A
×Do not use doses over 10,000iu a
day with Roaccutane
×Toxicity
Be Aware...
Niacin
Up to 500mg may enhance effects
of statins
But…
×High doses may increase risk of
myopathy
= So limit to 50mg
Be Aware...
Folic acid
× Anti-convulsants (e.g. Tegretol &
Epilim) may reduce folic acid
absorption
 So supplementation recommended
(refer to GP)
Methotrexate works by blocking folic
acid activation.
× Avoid folic acid with Methotrexate
Be Aware...
Vitamin E
× Care with aspirin
× Avoid high doses
Be Aware...
Vitamin K
× Avoid with anti-coagulants
CoQ10
× Avoid with anti-coagulants (similar
structure to Vit K)
Be Aware...
Calcium
× Care with calcium channel blockers
(e.g. Verapamil)
× May reverse blood pressure lowering
effects
Be Aware...
Potassium = elevated blood K levels with
×ACE inhibitors
×K-sparing diuretics
×NSAID indomethacin
×Antibacterial drugs (e.g. trimethoprim)
×Avoid ‘Lo-salt’ and ‘Solo’
Be Aware...
5-HTP
× Increases serotonin levels
× Avoid with SSRI’s unless under
medical supervision
Be Aware...
St John’s wort
×Contraceptive pill – may reduce effectiveness
×Migraine – increased incidence
×SSRI’s – side effects = nausea, confusion,
sweating, fatigue
×Theophylline
×Digoxin
×Warfarin
×Anti-convulsant drugs
×HIV meds
Be Aware...
Liquorice
×Glycyrrhizin stimulates production of
adrenal hormones and reduces
breakdown of steroids
×Risk of overdose with corticosteroids
or adrenaline meds
×Side effects with K-depleting
diuretics
 Use DGL
Key drugs-nutrient interactions...
1. Oral contraceptive pill
2. Anti-coagulants
3. Anti-depressants
4. Statins
5. Corticosteroids
Oral Contraceptive Pill
Q = What medication are
you on?
A = anti-depressants, blood
thinners, antacids,
painkillers…
Oral Contraceptive Pill
 Contraceptive
 Treatment of endometriosis, menstrual
irregularities
 Treatment of acne
Oral Contraceptive Pill
Depletion/interference…
×
×
×
×
×
×
×
Folic acid
Magnesium
Vitamin B6
Zinc
B vitamins (B1, B2, B3, B12)
Vitamin C
Manganese
Oral Contraceptive Pill
Possible increase in levels of…
 Iron (re. reduced menses)
 Calcium (re. increased absorption)
 Copper (re. increased absorption)
 Vitamin A (increased serum levels)
 Tobacco (increased damage)
Oral Contraceptive Pill
Supplementation
A good quality B complex
Magnesium
Zinc
Vitamin C (500mg)
Manganese
Liver support
Anti-coagulants
 Warfarin
 Aspirin
 Heparin
Anti-coagulants
 To slow rate of blood clot formation
 Prevention of blood clots after
surgery
 To dissolve blood clots
Anti-coagulants
Adverse supplement combination …
×Korean ginseng
×Devil’s claw
×Dong quai
×Fenugreek
×Garlic
×Ginger
×Gingko
×Horse chestnut
×Papain
×Quinine
×Red clover
×Vitamin D
×Vitamin K
×Vitamin E
×Fish oils
×Bromelain
×Feverfew
×Medicinal mushrooms
×Pau d’arco
Anti-depressants...
×5-HTP – side effects
×Korean ginseng – side effects
×St John’s wort – possible side effects
×Folic acid – low blood levels folic
acid = poor response to SSRI’s
(supplement 200mcg a day)
×Gingko – sexual dysfunction
×Alcohol – dizziness/drowsiness
Anti-depressants…
Supplementation…
Gingko (where appropriate)
Folic acid
Statins…
HMG- CoA reductase
inhibitors that block
production of cholesterol
Statins…
×coQ10 – deceased serum levels
×Niacin – possible myopathy at high doses
×Vitamin A – blood levels increased
×Fibre – oat bran & pectin – reduced
absorption
×Grapefruit juice – increase blood levels
Niacin – enhanced effectiveness of statins
(500mg 3 x day)
Vit E – statin +300iu vit E improved blood
vessel elasticity
Milk thistle – to reduce liver toxicity
Food – take with food (increase blood levels)
Corticosteroids…
×Magnesium – increased blood loss
×Potassium – increased blood loss – increase
K foods in diet
×Vit B6 – increased loss, so supplement to
prevent deficiency
×Vit D – reduced activation, so increased
possibility of bone loss
×Sodium – retention
×Liquorice – may increase side effects, re.
reduced liver clearance
×Alcohol – irritation to stomach
×Vit A - may reverse benefits of drug
Vit A
– may help wound healing
Advice for Practitioners…
Knowledge is power…
Keep informed…