Midterm Prep Flashcards
Define Pharmacotherapeutics
The use of drugs to prevent, treat and diagnose disease as well as to alter normal functions.
Define Pharmaceutics
The study of how various drug forms influence the way the drug affects the body.
List drug solubility from fastest to slowest acting
liquids, suspension solutions, powders, capsules, tablets, coated tablets, enteric-coated tablets
What is the pharmaceutical phase?
Drug dissolution
What is the pharmacokinetic phase?
Drug movement to achieve drug reaction (what body does to drug)
What is the pharmacodynamic phase?
How the drug changes the body (what drug does to body)
What are pharmacokinetics?
A D M E
Absorption
Distribution
Metabolism
Excretion
What are the routes of drug administration?
Enteral, Parenteral, Topical, Inhalation
What is enteral administration?
Oral, sublingual, rectal (GI tract)
What is Parenteral administration?
Intramuscular injection, subcutaneous injection, intravenous injection, intradermal injection, local injection.
What is topical administration?
Epidemic, instillation, irrigation
What is inhalation administration?
Vaporization, gas inhalation, nebulization
What is the most predictable route of administration?
Parenteral administration (injections)
What is absorption?
The movement of a drug from its site of administration into the bloodstream for distribution into the tissues.
What is bioavailability?
The amount of drug that is available after systemic circulation when it reaches the site of action.
What is bioequivalence?
When two medications have the same bioavailability and concentration of active ingredients. (When a trade name and generic drug are the same drug)
What is first pass effect?
The process that occurs in the liver that affects a drugs bioavailability.
High first pass effect = low drug bioavailability
What is the duration of action?
How long the medication works
What are factors that affect drug absorption enternally?
Food, fluids, blood flow, dosage formulation, GI motility, pH of drugs, molecular size (smaller molecules are more easily absorbed)
What factors affect absorption parenterally?
Solubility (lipid vs water soluble), surface area for absorption (smaller molecule size, easier absorbed.)
What is distribution?
The transport of a drug through the bloodstream to the site of action.
What is a drug-drug interaction?
Occurs when the presence of one drug decreases/increases the action of another drug.
What is the blood brain barrier?
A highly selective semi-permeable membrane made up of endothelial cells. It can make it more difficult for medications to penetrate the brain.
How many half lives does it take for a drug to leave your system? To reach a steady state?
5 half lives for a drug to leave, 5 half lives for drug to reach steady state.
What is steady state?
The even distribution of drug concentration
What is a loading dose?
A larger first time dose to get the patient to a state of therapeutic effect.
What is a maintenance dose?
Dosage that sustains therapeutic effect
How do we measure drug concentration?
We measure drug concentration in the plasma and assume it is the same concentration that is in the tissues.
Describe free drugs
Free drugs are pharmacologically active and cause an effect. They are used for short term effect.
Describe protein bound drugs
Protein bound drugs are not pharmacologically active and are used for slow release and long term effect.
What are concerns with potassium levels?
High potassium levels can cause cardiac arrhythmia or arrest.
What is drug interaction?
The modified action of a drug as a result of interaction to another drug, food, plant, herb or disease.
What is an adverse drug effect?
An undesirable drug effect that can range from mild to lethal.
What is drug incompatibility?
Chemical/physical reaction among two or more drugs in vitro (outside the body)
What is the most common form of drug interaction?
Pharmacokinetic
How do pharmacokinetic interactions affect absorption?
May results in increase/decrease of plasma drug concentration which enhances or reduces the effect of the drug.
How do pharmacokinetic interactions effect distribution?
It can cause increased or decreased drug effect and increased side effects. Free drugs will reach greater amounts of unintended receptors.
What do P450 inducers do?
Induces the P450 enzyme to metabolize the drug, even if it is a drug that was intended for later metabolizing. Inducers speed up metabolism.
What do inducers do?
Inducers cause subtherapeutic effects which means more medication is required to get a therapeutic dose.
What do inhibitors do?
Inhibitors can cause toxicity, a decreased dose would be required.
Is smoking an inhibitor or an inducer?
Smoking is an inducer
How do pharmacokinetic interactions effect excretion?
Any medication that can increase cardiac output or decrease blood flow to the kidneys can also decrease drug excretion (via urine).
What is synergistic effect?
When two drugs are given and one drug increases the effect (potentiates) the effect of the other.
What is antagonistic effect?
When a second drug cancels out or greatly diminishes the effect of the first drug. Example: antidote
What is a side effect?
Secondary drug effect can be undesirable but sometimes desirable. Often predictable, not dose related.
What is an allergic effect?
A non dose dependent effect that often occurs within several hours of contact with an irritant.
What is idiosyncratic effect?
Uncommon drug response. No real explanation for why it occurs and is often misunderstood. Can result from genetic pre-disposition