Pharmacology and Nutrition
summary
Chapter 1
Pharmacology: the discipline that deals with drugs. Pharmacology is the study of the effects of drugs
on the function of living systems. Nutrition can have positive effects on the prevention or treatment
of diseases or risk factors, but it can also have side-effects due to overconsumption of energy-dense
foods. The borders between nutrition and pharmacology are not sharp and tend to fade during the
last decades. The discussion on health claims for functional foods and food supplement remains a
matter of debate and controversy. One of the difficulties is that the definitions for claims are slightly
different around the world.
Medicinal product defined by presentation: any substance or combination of substances presented
for treating or preventing disease in human beings.
Medicinal product defined by function: “any substance or combination of substances which may be
administered to human beings with a view to making a medical diagnosis or to restoring, correcting
or modifying physiological functions in human beings.
The term drug often refers to the same as medicinal product. However, a single biologically active
compound is also often called a drug. Drug: a chemical substance of a known structure, other than a
nutrient or an essential dietary ingredient, which, when administered to a living organism, produces
a biological effect. Formulation: a combination of one or more active compounds (drugs) and one or
more excipients.
Medicinal products are extensively regulated by the EU and the national authorities. This includes
authorization procedures and rules for use, prescription etc. Medicinal products in the Netherlands
can be recognized from their RVG number. In the Netherlands, the Medicines Evaluation Board CBG-
MEB is responsible for this. Registration at EU level is performed by the European Medicines Agency.
A generic drug: a drug which is bioequivalent to a brand name drug with respect to pharmacokinetic
and pharmacodynamic properties. These products are usually cheaper than the brand name drug.
Generics are assumed to be identical in dose, strength, route of administration, safety, efficacy, and
intended use.
Functional foods: a category of food products that claims to provide some form of health benefit. EU
says that food can be regarded as functional if it is satisfactorily demonstrated to beneficially affect
one or more target functions in the body, to either improve health or reduce the risk of disease.
Health claim: any message or representation that states, suggests or implies that a relationship exists
between a food category, a food or one of its constituents and health (what does the food do?).
Nutrient claim: what is in the food (low in fat etc.). Recent EU legislation now allows claims relating
to reduction of disease risk or to children’s development or health. However, there are strict
regulations, and the authorities (EFSA) require solid scientific evidence that the
claim is substantiated. Article 14 list: of specific claims on specific products,
article 13 list: generally established function claims (calcium may be good for
your bones).
Misleading: if it refers to properties, which do not have any significance for the
overall intake of the nutrient in question (the claim "reduced fat" may not be
made for bread as bread is low-fat to start with).
Food supplements: foodstuffs of which the purpose is to supplement the
, normal diet and which are concentrated sources of nutrients or other substances with a nutritional
or physiological effect. Some vitamins are essential in small quantities but dangerous in large
quantities. With regard to the health claims they should comply with the same rules as any other
food.
An herbal product may only be called a herbal medicinal product when it fulfils the definition: “any
medicinal product, exclusively containing as active ingredients one/more herbal substances or
one/more herbal preparations, or combined.” Herbal medicinal products must be approved via the
normal drug approval procedures. It is possible to replace results of the pre-clinical tests and clinical
trials by detailed references to published scientific literature if it can be demonstrated that the active
substances of a medicinal product have been in well-established medicinal use within the Union for
at least ten years, with recognised efficacy and an acceptable level of safety. Most herbal
preparations available in Europe in pharmacies, drugstores, supermarkets and via Internet have not
been not approved as herbal medicinal products, Therefore, they should be called food.
Homeopathy is a specific system of therapeutics, based on the Law of Similars where "like cures like".
Diseases are treated by highly diluted substances that cause symptoms similar to those of the
disease to be treated. Homoeopathists use different explanations for the concept of homeopathy.
Homeopathy has in common with some other complementary medicinal concepts in being
personalised and regarding disease as an imbalance of an individual person.
Medical device: any instrument, apparatus, appliance, software, implant, reagent, material or other
article intended by the manufacturer to be used, alone or in combination, for human beings for one
or more of the following specific medical purposes.
Chapter 2
Toxicology: the study of the adverse effects of chemicals on living organisms.
Pharmacology can be divided into pharmacodynamics and pharmacokinetics. Pharmacodynamics:
what the drug does to the body, which involves molecular interaction of a compound with its target.
Pharmacokinetics: what the body does to the drug, the movement of the drug, time course of
absorption, bioavailability, distribution, metabolism and excretion (onset,
duration and intensity).
Pharmacotherapy: the actual treatment of patients with drugs.
In order to be absorbed, a drug needs to be in a dissolved state. At the site
of action, drug molecules interact with macromolecules, the receptors. In
many cases, receptors are normal regulatory structures and their natural
ligands (molecules that bind to a receptor) are neurotransmitters,
hormones or other signalling molecules.
Drugs bind by coincidence or by design to these receptors. A ligand
may activate or inactivate a receptor; activation may either increase or
decrease a particular cell function. Few, drugs are absolutely specific
for one receptor or subtype, but most have relative selectivity.
Selectivity is the degree to which a drug acts on a given site relative to
other sites. Most ligands bind to precise molecular regions, called
recognition sites, on receptor macromolecules. The binding site for a
drug may be the same as or different from that of an endogenous
agonist (hormone or neurotransmitter). Binding of a ligand that
activates the receptor leads to a sequence of processes, which is
translated to a response. The many steps between binding and final
cellular response are called signal transduction.
Cell-surface receptors: