Drugs And Pharmacology Lecture Flashcards
What is pharmacokinetics?
The study of the time course of a drug and its metabolites in the body after administration by any route.
What are the four main processes involved in pharmacokinetics?
- Absorption
- Distribution
- Metabolism (Biotransformation)
- Excretion
What is pharmacodynamics?
The study of the physiological effects of a drug on the body.
Name three factors affecting drug metabolism.
- Genetic factors
- Environmental factors
- Drug interactions
What is the therapeutic window?
The range of drug concentrations in the blood that provides the desired therapeutic effect without causing unacceptable toxicity.
What defines the lower limit of the therapeutic window?
The concentration that produces half the greatest possible effect.
What defines the upper limit of the therapeutic window?
The concentration at which no more than 5-10% of patients experience a harmful side effect.
What are agonists?
Drugs that bind to and activate cellular receptors, producing a biological response.
What are the types of antagonists?
- Chemical antagonists
- Functional antagonists
- Competitive antagonists
- Non-competitive antagonists
Define ED50.
The dose that gives the required response in 50% of subjects.
Define TD50.
The dose that produces harmful side effects in 50% of subjects.
What is the therapeutic index (TI)?
TD50/ED50. A larger TI reflects a greater margin of safety.
What is overdose toxicity?
Taking a drug above its therapeutic range.
What are side effects/sensitivities?
Unintended effects of a drug at therapeutic doses.
What are allergic reactions in the context of drug use?
The drug acts as an allergen/antigen, triggering an immune response.
What are drug interactions?
Occur when one drug affects the activity of another drug.
What is acetaminophen commonly known as?
Tylenol®
List possible mechanisms of action for acetaminophen.
- COX inhibition centrally
- Serotonin (5-HT) modulation
- Modulation of the endogenous cannabinoid system
What are the effects of NSAIDs?
- Anti-inflammatory
- Anti-pyretic
- Anti-platelet
- Analgesic
What is the main form of cortisone?
Cortisol (hydrocortisone)
What is the mechanism of action for opioids?
µ-opioid receptor agonists
What are the potential medical uses of opioids?
- Pain relief (acute, chronic)
- Sedation
- Anesthesia
- Cough suppression
- Diarrhea treatment
- Dyspnea
What are the two main compounds of cannabinoids?
- CBD (non-psychoactive)
- THC (psychoactive)
What is bioavailability?
The fraction of the administered drug dose that reaches the systemic circulation in an unchanged state.
What are the routes of drug administration?
- Oral
- Sublingual/buccal
- Inhaled
- Topical
- Vaginal
- Rectal
- Transdermal
- Injection (IV, IM, SC, IA)
What factors can affect drug distribution?
- Blood flow to target tissue
- Barriers like the blood-brain barrier
- Lipid solubility
- Binding to plasma proteins
What is the half-life of a drug?
The time it takes for the serum drug concentration to decrease by 50%.
What are common adverse drug reactions (ADRs)?
- Overdose toxicity
- Side effects/Sensitivities
- Allergic reactions
- Drug interactions
True or False: The therapeutic index (TI) is calculated by dividing TD50 by ED50.
True
