Intro to Drugs and Behaviour

Question Answer
For 476, what is a drug? * A drug is an exogenous chemical that binds to a receptor and initiates a physiological change.
What is behaviour? * Actions that you can observe/see in an animal such as motor activity, social activity, pain, approach/avoidance and also thoughts that you can talk about.
In you want to alter behaviour, you must alter the ….? CNS/PNS
Exogenous drugs are…? a chemical made outside the body
Endogenous drugs are..? a chemical made inside the body
What are the two approaches to studying drugs and behaviour? * 1. Drug taking can be examined as a behaviour e.g shooting up drugs, so study when and where person is taking the drug and why and who. 2. Look at how drug taking alters behaviour.
Discuss the two main approaches to studying drugs and behaviour. * see revision notes page one of book
How can we alter behaviour? (5 ways) * see revision notes page one of book
What are the 3 reasons we take drugs? * For a therapeutic effect, for a behavioural effect (therapeutically, behavioural effect, maliciously) and to satiate an addiction. See revision notes page one of book for complete answer with examples.
Differentiate between Abuse and Addiction * Abuse is when you are using more of the drug, more often with increasing problems such as missing work/school, financial problems, relationship problems, but you WON'T stop taking it. Whereas Addiction is when… see revision notes page one of book.
Is drug taking always a voluntary choice? *
Go over all of them in lecture notes.
No. situations: Enviro chemicals – floride in water, pesticides on veges, antibiotics in meat, second hand smoke. Unkowing consumption: roofies. Who/What influences us to take/not to take drugs? Parents, hospital/resthome staff, food providers, employees.
Describe Pharmacokinetics * Pharmacokinetics relates to how the drug moves into and throughout the body over time and the processes that occur during that journey (how your body handles the drug). Focuses on absorption, distribution, metabolism and elimination.
Describe Phamacodynamics * Pharmacodynamics relates to how the drug interacts with cellular receptors and alters cellular mechanisms. (What the drug does to your body, how it effects cells or larger organs)
Describe the two main devisions of pharmacology. * recall both descriptions together.
To get a drug into the brain, what obstacles need to be overcome? Consider different ROAs. * see revision notes page two of book
What are the five ROA? Oral, Sublingual, IV/IP/IM/SC, Inhalational, Insulation, Rectal, Transdermal
What are the pros and cons of oral ROA? * PRO: easy (anyone can swallow a pill), preferred ROA. CON: slow time of onset to get into bloodstream/brain esp.. when in fed state, has decreased bioavailability as a lot is broken down & metabolised so only some of it gets to brain, Peptides degraded.
What are the pros and cons of Sublingual ROA? * (putting under tongue). PRO: easy (anyone can do it) and faster onset than oral, better biolavailability than oral. CON: not many drugs can be absorbed this way.
What are the pros and cons of IV/IP/IM/SC ROA? * PRO: rapid onset anf optimal bioavailability. CON: once injected its non-reversible, not just anyone can do it (must be trained), is painful and aversive and has infection risk. You wouldn't want to inject a therapeutic drug for weeks.
What are the pros and cons of Inhalational ROA? * PRO: rapid onset as lungs have a large surface area so gets into blood fast, better bioavailability than oral. CON: not many drugs can be easily volatized, health risks if combusted – breathing in carcinogen (fire, smoke)
What are the pros and cons of Insulfation ROA? * (sniffing). PRO: faster onset and better bioavailability than oral. CON: damage to nasal tissue, can block vasculature, generally aversive.
What are the pros and cons of Rectal ROA? * PRO: better bioavailability than oral, useful of oral is not practical e.g. patient is vomiting, then give rectally. CON: generally aversive
What are the pros and cons of Transdermally ROA? * PRO: easy to stick sticker onto the skin, non-invasive or aversive CON: hard for drugs to get through the skin as the skin is designed to keep things out, not many drugs can do it.
What are the two epithelial cell barriers that drugs must cross to get into the bloodstream? (unless ROA is IV) * Cell barrier to get into tissue and cell barrier to get into vessel.
What types of drugs cannot cross cell membrane? * Large polar, amino acids and charged molecules.
What types of drugs can cross cell membrane? Small polar, gases, hydrophobic and lipophilic.
The smaller/more lipophilic a drug is, the better is will get into your …? bloodstream
What makes up the Blood-Brain Barrier? * The tight physical endothelial barrier + the plasma membrane barrier + extra efflux pumps.
What is the fourth obstacle after the drug has reached the brain? * Get the drug to bind to the right binding site.