Lecture 2 PCL201 Drug Basics
What is the difference between a drug and a toxin?
•may be used as a drug
• can cause harm.
•can be naturally produced
•can cause harm
•may be a toxin
What is a drug?
•Pills, cough syrup, injectables
•Cigarettes (nicotine and other compounds) coffee (caffeine: given to babies to
activate neonatal breathing response, athletes), wine (sedatives)
•Natural herbal compounds
•Recreational drugs (cocaine)
•A compound that changes, alters, or blocks a physiological/chemical process
•A substances intended for use in the diagnosis, treatment, mitigation, cure, or
prevention of disease in human beings or animals and a substance, other than food,
intended to affect the structure or any function of the body of a human being or
•Any substance that can be used to modify a chemical process or processes in the
body, for example to treat an illness, relieve a symptom, enhance a performance or
ability, or to alter states of mind.
•Pharmacology deals with the “desired” effect and toxicology deals with the
“adverse” effects or “poisonous effects”.
•It can replace (Agonist)/assist a natural chemical from the body. (Selective
Serotonin Reuptake Inhibitor – SSRI for depression)
oAlzheimer’s Disease (increase acetylcholine)
oParkinson’s Disease (increase Dopamine)
oBlocks the metabolism of neurotransmitters
oNormally neurotransmitter is released and received. Depression reduced
release. Prozac blocks reuptake of neurotransmitter, increasing the amount
of neurotransmitter in synaptic cleft, prolonging activity.
•It can be a novel compound that acts on a site in the body to activate or inhibit
something (Non-steroidal Anti-Inflammatory Agent – NSAID)
oNSAID blocks enzymes that form prostaglandins in cycloxygenase
E.g. Aspirin, Ibuprofen (Advil)
•It can change or block/inhibit formation of compound/chemical in body.