Chapter 7 - Medicines and Pharmacology Flashcards
Requirement for skin absorption?
Lipid solubility through the epidermis
Requirement for CSF absorption?
Nonionized, lipid-soluble drugs
Sulfonamides will do what in newborns?
Displace unconjugated bilirubin
What is 0 order kinetics?
Constant amount of drug is eliminated regardless of dose
What is 1st order kinetics?
Drug eliminated proportional to dose
How many half-lives for a drug to reach steady state?
5
Where are tetracycline and heavy metals stored?
In bone
Volume of distribution is equal to what?
Amnt of drug in the body divided by amnt of drug in plasma or blood
High volume of distribution means what?
Higher concentrations in the extravascular compartment compared with intravascular concentrations
What is bioavailability?
Fraction of unchanged drug reaching the systemic circulation; 100% for IV drugs
What is ED50?
Drug level at which desired effect occurs in 50% of patients
What is LD50?
Drug level at which death occurs in 50% of patients
What is tachyphylaxis?
Tolerance after only a few doses
What is potency?
Dose required for effect
What is efficacy?
Ability to achieve result without untoward effect
What is Phase I of microsomal drug metabolism?
Demethylation, oxidation, reduction, hydrolysis reaction (requries NADPH/O2)
What is Phase II of microsomal drug metabolism?
Glucuronic acid (#1) and sulfates attached (forms water-soluble metabolite)
Inhibitors of P-450?
Cimetidine, isoniazid, ketoconazole, erythromycin, Cipro, Flagyl, allopurinol, verapamil, amiodarone, MAOIs, disulfiram
Inducers of P-450?
Cruciform vegetables, ETOH, insecticides, cigarette smoke, phenobarbital, dilantin, theophylline, warfarin