Sig

Drug Enforcement Administration

Number

Usually required for schedule II-IV

Identifies prescriber as liscenced

Heading: 

Prescriber's Name, address, and Phone #

Patient Name, age (DOB), and Phone #

Date of Prescription

Body:

Symble Rx

Name and dose size or liquid concentration of the drug

Amount to be dispensed

Directions to the patient (Sig)

Closing:

Prescriber's Signature

DEA #

Refill Instructions

quid

tid

bid

4x/day

3x/day

2x/day

qd

qod

qid

every day

every other day

4x/day

FDA

(Food and Drug Administration)

FTC

(Federal Trade Commission)

DEA

(Drug Enforcement Administration)

Which schedule is this:

Highest abuse potential

Ex: Heroin, LSD, Marijuana, hallucinogens

No accepted medical use, experimental use, only in research

Which Schedule is this?

High abuse potential

Ex: oxycodone, morphine, amphetamine, secobarbital

Written prescription with provider's signature only, no refills

Which Schedule is this?

moderate abuse potential

ex: codeine mixtures (tylenol #3), hydrocodone mixtures (vicodin)

Prescriptions may be telephoned; no more than 5 refills in less than 6 mo.

Which Schedule is this?

Less Abuse Potential

Ex: Diazepam (valium), dextropropoxyphene forms (darvan)

Prescriptions may be telephoned; no more than 5 refills in less than 6 mo.

Which Schedule is this?

Least Abuse Potential

Ex: Some codeine-containing cough syrups

Can be bought OTC in some states

C. acetaminophen

Which is an example of a generic name?

a. Tylenol

b. Xyolocaine

c. acetaminophen

d. Valium

Administration by passing through the digestive szystem: oral and rectal

Ex: nitroglycerin

Administration bypassing the digestive system

ex: arestin

Absorption- the drug enters the body and is    absorbed

Distribution- the drug circulates w/i the body and is distributed

Metabolism- biotransformation, changing drug so it can be excreted

Excretion- how it leaves the body

lipids

proteins

carbohydrates

nonionized

lipid-soluble

When a drug is ____ soluble, it stays in the body longer.

ex: marcaine, Valium

C. More predictable response than intravenous administration

Advantages of oral administration of a drug include the following except: 

a. large surface area for drug absorption

b. many different dosage forms may be administered orally

c. more predictable response than intravenous administration

d. the simplest way to introduce a drug into the body

4-5

4-5

If the 1/2 life of a drug is 1 hour then in 4 or 5 hours the drug would be mostly gone from the body.  If the half life of a drug is 60 hours it would take 300 hours for that drug to be eliminated from the body.

liver enzymes are overwhelmed,

rate is constant over time, same amount of drug is metabolized and excreted per hour. Half life is dose related (aspirin, alcohol)

most drugs are changed to metabolites in the liver

metabolites are more ionized and less lipid soluble than the original drug

less reabsorption by kidney

less likely to bind to plasma or tissue proteins and be stored in fat

which effect is this?

Mechanisms of Metabolism

Active to inactive- doxycyline

Inactive to active- the inactive drug is transformed into the active drug, acyclovir is transformed w/i the cell

Active to Active- diazepam is metabolized into another active drug

Phase I- modification of drug involving P450 enzymes, occurs in the liver, if drug is still fat soluble goes on to phase II

Phase II- conjugation- forms a more polar drug that can be more easily excreted

b. duration

The half-life of a drug is most related to its:

a. onset

b. duration

c. safety

d. time to peak concentration 

ionization

lipid solubility

acidity of urine

-high pH- weak acids excreted more quickly

-low pH- weak bases excreted more quickly

Recycling through the liver by excretion in bile, reabsorption from intestines into portal circulation, with passage back into liver and re-excretion in bile.

Prolongs the effect of the drug.

Drug is finally excreted through the feces.

ex: digoxin and tetracycline

Goes from liver to gallbladder to GI tract.

amount of drug needed to produce an effect.

X axis of log dose

Effective Dose

(ED50)

The dose required to produce a specific effect in 50% of the subjects

or

 the dose that produces half the maximum effect

Lethal Dose

(LD50)

Therpeutic Index

(TI)

the LD50 divided by the ED50;

a measure of the safety of a drug,

the larger this is, the safer the drug

Useful in comparing drugs w/i a chemical class

ex: tylenol vs. aspirin

used to compare drugs w/ different mechanisms

ex: tylenol vs. morphine

c. have a greater curve height ( or higher on the Y axis)

Lower dose=higher potency

In comparing two drugs, the dose-response curve for the drug that is mroe efficacious would:

a. be closer to the y axis

b. be farther from the y axis

c. have a greater curve height

d. have a higher ED50

acetylcholine

norepinephrine/epinephrine

dopamine

serotonin

gamma-aminobutyric acid (GABA)

secreted to produce effects throughout the body, slower than neurotransmitters

changes things on long term basis

partial agonist- fails to produce maximal effects

weak agonist- must use many receptors

strong agonist- can use fewer receptors

antagonist

1. competitive

2. noncompetitive

3. physiologic

counteracts the action of the agonist

and 3 types

has an affinity for a receptor, combines with that receptor, and blocks it producing no effect

only effect is to decrease the effect of the agonist, no effect by itself

binds to a receptor site that is different from the binding site of the agonist

decreases the maximal effect or efficacy of the agonist

The drug Naloxone is used to reverse acute overdoses narcotics.  It binds to the same mu, kappa, and delta receptors that narcotics bind to.  Taken alone it has very few effects of its own.  This is an example of a:

a. agonist

b. partial agonist

c. competitive antagonist

d. physiologic antagonist