the study of how various dosage forms influence the way the body metabolizes drugs and the way in which a drug affects the body

the study of what happens to a drug from the time it is put into the body until the parent drug and all metabolites have left the body

the focus of pharmacokinetics is drug absorption into, distribution and metabolism within, and excretion from a living organism (ADME)

description of how a medication INFLUENCES physiologic processes in the body to provide a therapeutic benefit or mechanism of action

this occurs through either receptor interaction, enzyme interaction, or nonselective interaction

complex area applying medication knowledge (including pharmaceutics, pharmacokinetics, and pharmacodynamics) to specific patients and/or patient populations to treat disease and/or medical conditions

types of decisions can be divided into acute, maintenance, supplemental, palliative, supportive, prophylactic, and empiric

the amount of medication required by the body to produce a therapeutic benefit

acceptable dosing ranges are common and doses are often titrated within this range

some drugs have specific target doses for specific indications

undesirable response to medication that can occur when medication levels within the body are either therapeutic (within accepted treatment range) or elevated (toxic)

can be expected or unexpected (allergic reaction)

liquids, elixirs, syrups, suspensions, powders, capsules, tablets, coated tablets, enteric-coated tablets, sustained/controlled release oral formulations

the above are listed in order of fastest to slowest absorption rates 

administered by syringe, needle, or catheter as well as sublingual or buccal and avoid the GI tract

include IM, SQ, IV, ID, intra-articular, intra-arterial, and intra-thecal

IV and intra-arterial are considered to be 100% absorption

applied to the skin or mucous membranes for a localized target effect (e.g. eyes, ears, nose, rectum, vagina, and lungs)

include patches, creams, lotions, otic, opthalmalic, intranasal, inhalers, and suppositories

the movement of a drug from its site of administration into the bloodstream for distribution to the tissues

can be short or long processes depending on route of administration, dissolution rate, and medication characteristics

ends with all or a portion of the drug delivered to the systemic circulation and distribution begins

the amount or extent of drug available in the systemic circulation espressed as a percentage

it is effected by the route of administration

First-Pass Effect: liver enzymes metabolize the drug, decreasing the amount of active drug that reaches the systemic circulation thus decreasing bioavailability

Stomach pH, presence or absense of food, patients with portions of small bowel removed, certain medication use, conditions of low blood flow to the stomach or small intestine

refers to the transport of the drug in the body by the bloodstream to its site of action

once the drug is distributed, organs such as kidney and liver begin to metabolize and excrete the drug

drugs bind to protein in the blood such as albumin, alpha-1 acid glycoprotein, or corticosteriod-binding globulin and these bound drugs are considered pharmacologically inactive as opposed to unbound, "free" drugs

low albumin levels require lower drug dosages; drugs can compete for protein-binding sites and one drug may have a higher "free" drug level than expected

water-soluble drugs typically remain in the bloodstream and have a smaller volume of distribution

fat-soluble drugs typically leave the bloodstream to reach further targets and have a larger volume of distribution

involves the biochemical alteration of a drug into an inactive metabolite, a more soluble compound, or a more potent active metabolite

cytochrome P-450 enzymes in the liver control biochemical reactions involved in drug metabolism and typically target lipid soluble drugs

excretion of drugs by the intestinal tract in which drugs are taken up into the liver, released in the bile, and eliminated in the feces

state in which the amount of drug removed via elimination is equal to the amount of drug absorbed with each dose and typically occurs after 4-5 half lives

once a steady state is achieved, there are consistent levels of drug in the body that correlate with maximum therapeutic benefits

medications are attracted to cell surfaces based on the chemical structures of the medication and the receptor site

when medications bind to a receptor, physiologic processes are affected by either eliciting a cellular response (agonist) or blocking a cellular response (antagonist)

drugs that are most effective are those that mimic endogenous substances