Pharm Homework
Pharmacology Basics
Pharmacology: Branch of medicine focusing on the uses, effects, and modes of action of drugs.
Core Concepts
Pharmacokinetics: Studies movement of drugs within the body.
Pharmacodynamics: Describes the extent and duration of a drug's action within the body.
Off-label Use: Referring to the prescription of drugs for conditions other than those for which they have been officially approved.
Drug Movement and Administration
Absorption: Process of drug movement from the site of administration to systemic circulation.
Distribution: Reversible transfer of a drug from one location to another within the body.
Types of Medications
Enteral Medications: Administered through the gastrointestinal tract. Examples include:
Oral meds (e.g., pills)
Sublingual (SL) meds
Buccal meds
Rectal meds
Parenteral Medications: Administered by routes other than the GI tract. Examples include:
Subcutaneous (SQ)
Intramuscular (IM)
Intravenous (IV)
Drug Dosage Terms
Dose: Specific quantity of drug (e.g., single dose or total daily dose).
Dosage: Specific amount and frequency of medication; includes how often and how it’s administered.
Loading Dose: Higher initial dose to rapidly achieve adequate levels of the drug in the bloodstream.
Key Pharmacological Terms
Half-life: Time for drug concentration in the bloodstream to decrease by half.
First-order kinetics: Drug elimination rate is proportional to its concentration in the body.
Zero-order kinetics: Drug elimination rate is constant and independent of concentration.
Pharmacokinetics and Drug Properties
Bioavailability: Fraction of an administered drug that reaches systemic circulation in active form.
Metabolism: Process by which the body breaks down and converts medications into different chemical forms.
Onset of Action: Time for a drug to begin its therapeutic effect.
Duration of Action: Length of time a drug remains effective after administration.
Therapeutic Index: Measure of a drug's safety.
Drug Concentration and Interaction
Peak: Highest concentration of a drug post-administration.
Affinity: Strength of interaction between a drug and its receptor.
Efficacy: Ability of a drug to produce the desired therapeutic effect.
Potency: Amount of drug needed to produce a specific effect.
Summation: Combined effect of two or more drugs or stimuli.
Synergism: When combined drugs produce an effect greater than the sum of their individual effects.
Potentiation: One drug enhances the effect of another without producing an effect on its own.
Tolerance: Reduced response to a drug after repeated use.
Drug Action Mechanisms
Receptors: Specific proteins on cell surfaces that interact with substances to elicit biological responses.
Agonist: Substance that binds and activates a receptor, mimicking the action of a natural neurotransmitter.
Antagonist: Binds to a receptor but does not activate it. Blocks action of agonists.
Types of Receptors
Adrenergic Receptors: Respond to catecholamines, involved in muscle contraction and heart rate modulation.
Cholinergic Receptors: Activated by acetylcholine; includes:
Nicotinic Receptors: Found at neuromuscular junctions, stimulate acetylcholine release.
Muscarinic Receptors: Found in smooth muscles.
Medication Administration Considerations
Nine Rights of Medication Administration: Patients should verify the following before administration:
Right Patient
Right Medication
Right Dose
Right Route
Right Time
Right Documentation
Right to Education
Right to Refuse
Right Response
Schedules of Controlled Substances
Schedule I: High abuse potential, no medical purpose (e.g., heroin, LSD).
Schedule II: High abuse potential, recognized medical purpose (e.g., opioids).
Schedule III: Lower abuse potential than Schedule II (e.g., certain stimulants).
Forms of Medications
Form | Brief Description | Examples |
|---|---|---|
Capsule | Med enclosed in dissolvable gelatin capsule | Opioid cough meds |
Tablet | Solid medication in a desired shape | Tylenol, Aspirin |
Parenteral solution | Sterile solution for injection | Fentanyl |
Skin preparation | Designed for transdermal absorption | Gel, ointment |
Complications of IV Starts
Hitting an artery
Blowing a vein
Infiltration
Needle stick injury
Important Medications for Study
Essential drugs to memorize for the exam include:
Dextrose
Nitroglycerin
Epinephrine
Albuterol
Aspirin
Naloxone
Amiodarone
Others include Norepinephrine, Dopamine, Onancestron, etc.
Additional Drug Calculation Scenarios
Be prepared for various calculations like dosages, concentrations, and volumes of medications under specific conditions, particularly relevant for dosages in pediatric and emergency cases.