Principles of Pharmacology Flashcards
Pharmacotherapy
Study of drugs defined as treating or preventing disease and the alleviation of pain and suffering
Pharmacodynamics
What the drug does to the body at a molecular level
Pharmacokinetics
Movement of the drug into, through and put of the body. Absorption, bioavailability, distribution, metabolism and excretion. What the body does to the drug
Autonomic Nervous System
Control system that acts largely unconsciously and regulates bodily functions such as heart rate, digestion, respiratory function, pupillary response, urination and sexual arousal. Also controls fight or flight response
What 3 types of drug names are there?
Chemical, Generic. Trade name
Bioavailability
Proportion of the administered dose that reaches the system circulation intact and ready for action
Clearance
The volume of blood cleared irreversibly of drug over time. How quickly the drug can be eliminated by the body
Volume of distribution
The volume in which the amount of the drug in the body would need to be uniformly distributed to produce the desired concentration in the blood
Half-life
How long it takes for the blood or plasma concentration of the drug to fall below 50 percent
What are the four components of Pharmacokinetics?
Absorption, Distribution, Metabolism, Excretion
What factors affect Absorption?
Rate of dissolution, surface area, blood flow, lipid solubility, hepatic-first pass effect (liver filtration)
What are the factors affecting Distribution?
Blood flow to tissues, drug’s ability to exit the vascular system, drug’s ability to enter the cells, protein binding, blood brain barrier
What are the factors affecting Metabolism?
Age, nutritional status, competition between drugs. first pass effects
What are the therapeutic consequences of drug metabolism?
Accelerated renal drug excretion, increased therapeutic action, drug inactivation, increased or decreased toxicity
Where in the body can drugs be eliminated?
Liver, kidneys.
By urine, bile, sweat, saliva, tears, milk and stool
What are the 3 main ways drugs can cross cell membranes?
Through channels and pores, with aid of transport system, direct penetration of the membrane itself
What are transporters?
Carriers that move ions or small molecules from one side of the cell membrane to the other
What are enzymes?
Substances that speed up chemical reactions by lowering a reaction’s activation energy.
What are ion channels?
Pores that open or close to control the movement of ions in and out of cells
What are receptors?
A large group of proteins that are targets for drugs. The combination creates a drug-receptor complex which creates the desired response
What are adrenoceptors?
A class of receptor that is stimulated by the transmitter noradrenaline that is linked to the ANS
What’s an agonist?
A drug that binds to a receptor to produce an effect
What’s an antagonist?
Drugs or chemicals that bind to receptors but do not activate them. This produces no biological effect and can block or reverse the effects of agonists
What are the two division of the ANS?
Sympathetic: Fight or flight, mobilises body systems
Parasympathetic: Rest and digest, conserves energy
What are the 4 kinds of adrenergic receptors?
Alpha 1 and 2
Beta 1 and 2
Alpha 1 effects
Vasoconstriction (increased BP), pupil dilation, decreased GIT activity, glycogen breakdown (BGL increase), urinary retention, smooth muscle contraction, sweating
Alpha 2 effects
Inhibits further release of the transmitter hence inhibiting sympathetic activity
Beta 1 reaction
Increase heart rate, lipolysis or breakdown of fat, decrease GI motility, triggers the renin-angiotensin-aldosterone system
Beta 2 reaction
Bronchodilation, vasodilation, glycogen breakdown, relaxation of pregnant uterus
What happens when a cholinergic nerve is stimulated?
Acetylcholine is released which activates muscarinic receptors to trigger an effector response. It causes increased gastric acid secretion, increased GI motility, pupillary constriction, decreased heart rate, bronchoconstriction, decreased heart rate, promotion of urination and defecation AKA rest and digest
What steps are involved in checking it’s safe to administer via IV?
Check for systemic complications such as too much or too little fluid volume caused by unbalanced flow rate. Check for air embolism caused by air in the line, Monitor for infection or clotting at the injection site. Undertake documentation and medicine checking. Ensure line is flushed before and after medicine to ensure patency
What’s a PICC?
Peripherally Inserted Central Catheter
What’s a CVC?
Central Venous Catheter
What are the indications for PICC or CVC?
Long term IV antibiotic use, TPN administration, poor peripheral access, inotrope administration, situations where large volumes of fluid need to be administered, drugs which cause phlebitis when administered peripherally
PICC use duration
3-6 months
CVC use duration
7-14 days
