Introduction to Pharmacology Flashcards
What is the role of the FDA in governing medications?
Controls drug development process, approves marketing of new drugs, approves new uses for older drugs.
What is the dose-response relationship in pharmacotherapeutics ?
The relationship between the dose of a drug and the magnitude of its effect.
What is the ceiling effect in dose-response?
The point at which increasing the dose does not increase the effect.
What is drug potency?
The amount of the drug required for a given response.
What are pharmacokinetics?
The study of what happens to a drug once it is in the body:
- absorption
- distribution
- metabolism
- excretion
What is drug absorption?
Drug Absorption: The process by which drugs are transferred from administration to systemic circulation.
Bioavailability: The percentage of a drug that reaches systemic circulation from the site of administration.
What are the advantages of oral administration of drugs?
Most common method, easy to administer, allows for gradual increase in drug levels.
What is the first-pass effect?
Metabolism and degradation of a drug by the liver before it reaches systemic circulation.
What is sublingual and buccal administration?
- Sublingual: Administration of a drug under the tongue.
- Buccal: Administration of a drug between the cheek and gums.
What are the advantages of rectal administration?
Bypasses the liver, useful when oral administration is not possible.
What are the advantages and issues with inhalation administration?
Large surface area of lungs allows for rapid systemic circulation, but can cause respiratory irritation.
What are the various forms of injection administration?
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- Intravenous: into the peripheral vein for rapid entry to bloodstream to target tissue; 100% bioavailability.
- Intra-arterial: directly into an artery allows for direct travel to tissue without affecting other tissues
- Subcutaneous: injection directly under the skin for local response or slower, more prolonged release into the system such as insulin.
- Intramuscular: directly into skeletal muscles for localized muscularproblems (botulinum toxin for spasticity)
- Intrathecal: into a sheath, example of subarachnoid space in spinal meninges (local analegics)
What are the risks of injection administration?
Risk of infection due to breaking the skin barrier.
What is topical administration?
Application of medication to the skin or mucous membranes.
What is transdermal administration?
- Advantages = ?
- Application of medication directly to the skin for absorption into systemic circulation.
- Slow, controlled release of medication, avoids first-pass effect.
What is iontophoresis?
Use of electrical current to drive medication through the skin.
What is phonophoresis?
Use of ultrasound to drive medication through the skin.
How does exercise affect drug absorption?
Exercise can increase drug absorption by increasing blood flow and temperature.
What is drug distribution?
The process by which a drug is distributed to different parts of the body.
What factors affect the rate of drug distribution?
Organ blood flow, tissue permeability, binding to plasma proteins, binding to subcellular compounds.
Where are drugs stored in the body?
Adipose tissue, bone, muscle, organs.
What are…
- controlled-release medications = ?
- implanted drug delivery systems = ?
- target drug delivery to specific cells = ?
- Controlled-release medications: Medications designed for slower and more prolonged absorption and delivery.
- Implanted drug delivery systems: Small container placed under the skin that releases medication on a preprogrammed schedule.
- Target drug delivery to specific cells: Medications modified to only activate at target tissues.
What is biotransformation?
Another term for drug metabolism, involving chemical changes to drugs in the body.
What are the types of biotransformation reactions?
- oxidation
- reduction
- hydrolysis
- conjugation
Where is the primary location for drug metabolism?
The liver, due to its abundance of metabolizing enzymes.
What are the primary sites for drug excretion?
Kidneys, with additional excretion through lungs, GI tract, sweat, saliva, breast milk.
What factors affect drug excretion rate?
Vascular flow, pH changes, hydration levels, temperature changes.
What is drug clearance?
The ability of an organ or tissue to eliminate the drug from the plasma.
What is drug half-life?
Half-Life: The amount of time required for 50% of the drug to be eliminated from the body.
What are pharmacodynamics?
The study of how drugs affect tissues at the molecular and cellular levels.
How do drugs affect tissues at molecular and cellular levels?
- acting as ion channels
- influencing enzymatic function
- linking to regulatory proteins
What are ion channels in pharmacodynamics?
Receptors that alter cell membrane permeability by acting as ion channels.
What are examples of receptor drugs?
Muscarinic acetylcholine, dopamine, norepinephrine, hormones.
How do drugs act enzymatically in pharmacodynamics?
Drugs can change enzyme activity within the cell to promote or inhibit function.
What are G-proteins and secondary messengers?
G-proteins are intermediate regulatory proteins that alter intracellular activity and mediate drug responses.
What is the dose-response relationship in pharmacodynamics?
Related to the number of receptors bound by the drug; more receptors result in a larger response up to a maximum effect.
What is drug selectivity?
A drug’s ability to affect only one type of cell or tissue for a desired response.
What is an agonist in pharmacodynamics?
A drug that binds to a receptor and activates it to produce a response.
What is an antagonist in pharmacodynamics?
A drug that binds to a receptor but does not activate it, preventing other compounds from having an effect.
How does age affect pharmacotherapeutics?
Age affects both pharmacokinetics and pharmacodynamics, with older adults experiencing increased sensitivity and altered drug metabolism.
How do liver and kidney diseases affect pharmacotherapeutics?
These diseases can slow drug metabolism and elimination, increasing the risk of adverse reactions.
How does exercise affect pharmacotherapeutics?
Exercise can affect drug absorption, distribution, metabolism, and excretion, often increasing absorption and distribution.
What are the different types of drug nomenclature?
Chemical name, generic name, and trade (brand) name.
What are common drug abbreviations?
Common abbreviations include
- a (before)
- bid (twice/day)
- h (hour)
- IM (intramuscular)
- IV (intravenous)
- prn (when needed)
- q (every)
- TID (three times/day)
How do you understand prescription medication labels?
Prescription labels include the patient name, drug name, dosage, instructions, and expiration date.
What is the difference between prescription and over-the-counter medications?
Prescription medications require a doctor’s order, while over-the-counter medications can be purchased without a prescription.
- What are controlled substances ?
- Schedule I-V drugs ?
Drugs classified by their potential for abuse and dependence.
What is the therapeutic index (TI)?
A measure of a drug’s safety, calculated as the ratio of the median toxic dose to the median effective dose.
What are drug-drug and food-drug interactions?
- When two drugs interact to alter each other’s effects, either diminishing or enhancing them.
- When foods alter drug absorption or metabolism, e.g., grapefruit juice and certain medications.
What are adverse drug reactions (ADR)?
Unintended or unwanted effects of a drug that occur at normal dosage levels.
What are adverse drug events (ADE)?
Any event that can go wrong when administering a drug, including prescribing errors, dosing errors, and ADRs.
What are common side effects of drugs?
Expected reactions that occur with predictable frequency and may or may not be adverse.
What is drug toxicity?
The negative effects of chemicals, often occurring at high doses.
What causes adverse drug reactions?
Narrow therapeutic index drugs, clinician-related factors, and patient noncompliance.
What are potential compliance issues with medications?
Issues include difficulty opening containers, fear of choking, misreading labels, cognitive impairment, and cost of medication.
What is polypharmacy?
The use of five or more medications, often leading to excessive or contraindicated drug use.
What are the concerns with polypharmacy in geriatric populations?
Side effects are often misinterpreted as aging, multiple doctors may prescribe conflicting medications.
How can adverse drug reactions be identified?
Look for symptoms that match known ADRs, consider timing and dosage changes.
What is the Naranjo ADR probability scale?
A tool used to assess the probability of an ADR, with scores ranging from 0 (doubtful) to 10 (definite).
What are the types of drug allergies?
- anaphylactic
- cytotoxic
- autoimmune
- cell-mediated hypersensitivity
What is anaphylactic reaction?
A severe, immediate allergic reaction causing cardiovascular and respiratory collapse.
What is cytotoxic reaction?
A reaction that destroys target tissue, occurring over days to weeks.
What is autoimmune reaction?
An inflammatory response due to difficulty eliminating drug complexes, resolving after drug discontinuation.
What is cell-mediated hypersensitivity?
A local or tissue reaction, such as contact dermatitis.
What are the parameters to monitor when using medications?
- therapeutic uses
- side effects
- contraindications
- drug interactions
