1. NUTRITIONAL PHARMACOLOGY pgs1-25 ↓ ↑ Flashcards
This module covers: • Drug restrictions, administration and metabolism. • Side effects of drugs. • Drug-nutrient interactions. • Drug-induced nutrient depletions. • Major groups and actions of pharmaceutical drugs. • Pharmaceuticals and the nutrition consultation.
NTs need to know about a drugs side effects & interactions.
why?
- Clients often use a complex prescription and OTC drugs.
- Every drug has side effects e.g., gastric ulceration if taking ibuprofen.
- Food or supplements may interact with a drug causing things like ↑ bleeding risk with warfarin and vitamin E.*
- Drugs can lead to important nutrient depletions e.g., metformin and vitamin B12.
What is a ‘medicine’ (MHRA).
MHRA = Medicines & Healthcare Products Regulatory Agency
Any substance or combination presented as having properties for treating or preventing disease in humans.”
OR
“Any substance or combination which may be used in, or administered to, human for
restoring,
correcting or
modifying physiological functions by exerting a
pharmacological,
immunological or
metabolic action, or
to making a medical diagnosis.”
Restrictions - Intended mode of Action must have what?
a regulatory licence detailing their intended mode of action.
How are medicines supplied?
Prescription only (POM) — doctor’s prescription.
- Controlled medicines — medicines requiring extra controls e.g., codeine, morphine.
- Pharmacy only (PO) — pharmacy only
- General sales list (GSL) —lots of outlets including supermarkets.
Name the OTC legal distinguished routes used for self-medication of minor ailments?
OTC = over the counter
-
PO (Pharmacy only)
sold and supplied under pharmacist supervision. -
GSL (General sales list)
sold by a pharmacy and other shops
Why might clients choose to self-medicate?
- To treat a MINOR ailment e.g., a cough mixture.
- To support a CHRONIC ILLNESS if not fully controlled by their prescription eg.., ibuprofen for osteoarthritis.
alpcad
Match the drug to the OTC class
a) codeine, paracetemol, aspirin, ibuprofen
b) bisacodyl, senna
c) Omeprazole
d) Diphen hy dramine (written phonetically)
e) Chlorphen amine, Cetirizine (phonetically)
f) pseudo ephedrine
a) Analgesic
b) Laxative
c) Proton pump inhibitor
d) Cough Mixture
e) Anti Histamine
f) Decongestant
What’s in the ACTIVE INGREDIENTS of a drug?
it ‘s intended to deliver its mode of action and is responsible for side effects e.g., ibuprofen to reduce inflammation.
What’s in the INACTIVE INGREDIENTS of a drug?
These alter the physical properties of the drug e.g.,
fillers,
colouring agents,
preservatives,
lactose,
gluten,
aspartame,
other E numbers.
Studies show inactive ingredients trigger allergic reactions and food intolerances.
In terms of how drugs are described, what is meant by the following:
a) Generic name
b) Brand name
Generic name:
This is the actual active ingredient within the drug (NTs must look for this)
e.g., paracetamol (Europe), acetaminophen (US). Paracetamol and acetaminophen are the same active ingredient.
Brand name:
Paracetamol comes under other branded names e.g., Panadol (UK), Tylenol (US).
A nutritional therapist must always look for the generic name.
Explain the following drug terminology:
a) Drug class
b) Indication
c) Contraindication
d) Side effects
e) Interactions
a) drug class - penicillin is an antibiotic
a) Indication: What it’s intended for, e.g., hypertension (high blood pressure).
b) Contraindication: When drug must NOT be used e.g., in pg, renal failure.
c) Side effects: Ibuprofen can cause gastric ulcers.
d) Interactions: A drug’s activity is affected by another substance causing an increase, decrease or a new effect.
Drugs VS Nutrients ?
Drugs suppress and manage symptoms (and don’t target the root cause) whilst nutrients encourage the body to restore homeostasis and heal.
paracetemol - manages a tension headache VS client is stressed (cause)
Topical corticosteroid ( atopic eczema) treats the symptom VS flares with gut dysbiosis
Laxatives - manage constipation VS client has low stomach acid and low digestive enzymes
what is aspirin derived from and how does it differ from the whole plant?
Aspirin is derived from willow bark (Salix alba) an ancient herb.
- Willow bark contains salicin, doesn’t convert to salicylic acid (irritates the gut) , reaches the bloodstream and body tissues. It NATURALLY reduces fever, inflammation and pain without GI side effects.
Aspirin was synthetically developed from salicylic acid. but causes GIT bleeding, peptic ulcers & hypersensitivity (aspirin ignores the whole unit of the plant)
- Willow bark has lots of active components all influence each other and in totality contribute to its overall healing potential.
Define the following terms:
pharmacokinetics
pharmacodynamics
a) Pharmacokinetics - movement of drugs in the body.
b) Pharmacodynamics - how they interact WITH the body to exert their effects.
Which four key processes is involved in pharomacokinetics?
Hint: ADME
ADME
ABSORPTION,
DISTRIBUTION,
METABOLISM and
EXCRETION
of a drug
what’s ‘First Pass Hepatic Metabolism’ in the administration of certain drugs?
Drugs taken orally, absorbed from the GIT, taken via the portal vein to the liver to be metabolised. By the time it enters SYSTEMIC CIRCULATION, when it’s extensively metabolised, amount that reaches blood stream is TINY - needs different route eg., GTN spray - angina.
2 factors determine if it reaches target site of action, what are they?
- Bioavailability and
- Route of administration
Bio-Avail -proportion that gets to the blood stream and available for distribution to its intended site of action.
Route of admin - How? drug is administered e.g., oral tablets, sublingual B12, suppository, injectables, topical creams, patches, all directly influence the medicine’s bioavailability.
Expand on what the following routes of drug administration entails:
a) Oral
b) Sublingual
c) Buccal
d) Topical
e) Parenteral
a) Oral: Tablets, capsules, liquids. Absorption is mainly via the SMALL INTESTINE.
b) Sublingual: Sprays, tablets, films under the tongue (e.g. gtn spray) and directly absorbed into the blood (bypasses liver metabolism).
c) Buccal: Tablets placed between the gum and inner cheek and directly absorbed into the bloodstream (e.g. prochlorperazine maleate tablets).
d) Topical:
‒ Local effect: Creams, patches (Cutaneous route), ear (Otic route) and eye (Ocular route) drops.
‒ Systemic effect: Inhalation (Pulmonary route = rapid effects).
e) Parenteral: Injections: Intravenous, sub-cutaneous, intra-muscular. Avoids the intestines and bypasses liver metabolism.
List three factors, related to the body, that can affect the absorption of a drug.
- Gastro-intestinal motility: Diarrhoea increases motility and reduces absorption.
- Malabsorption states reduce absorption e.g., Coeliac disease.
- Presence of other substances: E.g., absorption of iron is reduced when given with milk.
Which characteristics of a medicine might enhance its absorption?
- Absorption is greatest for lipid soluble and small molecule drugs.
- Acidic drugs absorb quicker in an acidic environment e.g., stomach.
- A liquid medicine will absorb quicker than a solid tablet.
After a drug enters the systemic circulation, it is distributed to the body’s tissues.
List three factors that can affect this distribution.
The distribution of a drug is affected by a number of factors:
- Binding to plasma proteins which affects the active concentration of the drug.
- Binding to other tissues e.g., tetracycline (antibiotic) binds to calcium in bones and teeth.
- Accumulation in lipids e.g., general anaesthetics.
- Natural barriers to distribution e.g., blood brain barrier, placental barrier.
Define: ‘Drug metabolism’
The process by which drugs are chemically changed from a lipid soluble to a more water-soluble form suitable for excretion
so what happens in drug excretion?
drugs and their METABOLITES are removed from the body
What are the main excretion routes?
Urine and faeces
What are the minor excretion routes?
Exhales air, sweat, saliva, tear
With renal excretion, what does it normally pass through for elimination?
Small water-soluble MOLECULES
With renal dysfunctio, what happens
It affects the rate at which a drug/metabolite is clearned from the body
What would happen with a very lipid soluble drug?
that drug may be re-absorbed and re-enter the portal vein. This is known as entero-hepatic circulation’ and prolongs excretion times.
