General Principles of Pharmacology Flashcards
Pharmacokinetics
Activity of a drug in the body over time (branch of pharmacology concerned with the movement of drugs within the body) study of the bodily absorption, distribution, metabolism, and excretion of drugs (how body effects drug)
Absorption
Refers to the way a drug is absorbed from a pharmaceutical formula into the blood stream, moving from its “site of delivery into the bloodstream,”
journey of a drug travelling from the site administration to the site of action
Distribution
Refers to the movement of a drug to and from the blood and various tissues of the body (process of transferring a drug from the bloodstream to tissues)
Metabolism
Is the chemical alteration of a drug by the body (breakdown of drug) break down and coverts medication into active chemical substance
First-pass effect
Drug gets metabolized at a specific location in the body that results in a reduced concentration of the active drug upon reaching its site of action
Therapeutic index
Is a ratio that compares the blood concentration at which a drug causes a therapeutic effect to the amount that causes death (margin of safety that exist between the dose of a drug that produces a desired effect and the dose that produces an unwanted side effect)
Half-life
the time it takes for the amount of a drugs active substance in the body to reduce by half
Pharmacodynamics
The relationship between drug concentration at the site of action and the resulting effect (what the drug dose to the body) how the drug effects the body
Agonist
A drug or substance that binds to a receptor inside a cell or on its surface and causes the same action as the substance that normally binds to the receptor
Antagonist
A substance that stops the action or effect of another substance (acts against and blocks and action)
Synergistic effect
Interaction of two or more drugs when their combined effect is greater than the sum of the effects seen when each drug is given alone
Therapeutic drug monitoring
Testing that measures the amount of a certain medicine in the blood (measuring of drug levels in the blood at timed intervals to maintain relatively constant levels
Adverse effects
Harmful or abnormal result
Toxicity
How poisonous or harmful a substance can be (occurs when person accumulated too much of a drug in the bloodstream, leading to adverse effects on the body)
Hepatotoxicity
The injury/ Liver damage caused by exposure to drugs
Nephrotoxicity
Rapid deterioration in the kidney function due to toxic effects of medications and chemical
Anaphylactic reaction
Severe, potentially life-threatening allergic reaction
Extrapyramidal symptoms
Commonly referred to as drug induced movement disorders (group of symptoms including tremor, slurred speech, anxiety, distress, paranoia etc.)
Immunosuppression
suppression of the body’s immune system and its ability to fight infections an other diseases
What role does albumin play in medication distribution
Albumin possesses specific sites for acidic and basic drug binding
It is a natural transport protein w/ multiple ligand bind sites
Most abundant plasma protein in he body
What role does glycoprotein play in medication distribution
“Multi drug transport protein”
Transports a wide variety of drugs OUT of cells
KIDNEY- pumps drugs into urine for excretion
INTESTINE- transports drugs into the intestinal lumen, reducing drug absorption into the blood
BRIAN- pumps drugs into the blood theory limiting drug access to the brain
Types of drug interactions
1) drug-drug: interaction between row or more prescriptions
2) drug- nonprescription: drug w/ other over the counter, herbs or vitamins
3) drug-food: food/beverage alters drug effect
4) drug-alcohol:
5) drug-disease:
6) drug- laboratory: some drugs can interfere w/ test
Excretion
Movement of drugs and their metabolites out of the body
The rate of absorption determines
How soon effects will begin
The amount of absorption help determine
How intense effects will be
Absorption includes
Rate of dissolution: must first be dissolve before absorbed (rate of dissolution determine rate of absorption)
Surface area: larger surface area, equals faster absorption
Blood flow: absorbed most rapidly from sites where blood flow is high (greater concentration gradient, more rapidly absorption will be)
Lipid solubility: highly lipid soluble drugs are absorbed more rapidly than drugs who’s lipid solubility is low (bc lipid soluble drugs cross membranes and low lipid soluble can not)
Selectivity
Ability to elicit only the response for which the drug is given
The more selective a drug is the fewer side effects it will produce
Selective drug action is possible because drugs act through specific receptors
Affinity
Refers to the strength of the attraction between a drug and its receptor
Intrinsic activity
Ability of a drug the activate a receptor upon binding
Consequences of drug-drug interactions
1) One drug may intensify the effect of the other
2) One drug may reduce the effect of the other
3) The combination may produce in the response not seen with either drug alone
Drug-food interaction
Food decreases the rate of absorption and occasionally decreases the extent of exception
Idiosyncratic effect
A uncommon drug response resulting from a genetic predisposition
Paradoxical effect
Opposite of the intended drug response
Iatrogenic disease
Disease resulting from medical care or treatment
Teratogenic effect
Drug induced birth defect
