Chapter 3 (drug forms and administration)

Question 1

Rare ways of administering drugs

Answer 1

intra-arterial, intra-articular, intracardiac, intradermal, intrathecal, via umbilical artery or vein

Question 2

Elixir

Answer 2

medicine containing active ingredient (such as morphine) dissolved in solution that contains ethyl alcohol and is taken orallly

Question 3

Tincture

Answer 3

very similar to elixirs, but have higher alcohol percents and must be applied topically

Question 4

tablet coating purposes

Answer 4

make tablet easier to swallow
enteric coating protects active ingredient from stomach pH and make it only absorbed in certain areas
control rate of release to release it over time

Question 5

generic drug strength

Answer 5

must have strength between 75 and 125% of brand name drug, but binders in drug can be different so different kinetics may be seen even though strength is similar

Question 6

infatab

Answer 6

chewable tablet with pediatric dose of medication (ex. phenytoin infatabs prevent epileptic seizures in infants and children)

Question 7

spansule

Answer 7

capsule with little time-release beads inside

Question 8

Tembid

Answer 8

long-actin bid formulation of oral nitroglycerin is called Isordil Tembid Tablet, extended release

Question 9

sublingual

Answer 9

placement below tongue; valuable for patients who don’t want to or can’t swallow
nitroglycerin is most common b/c of heavy 1st pass effect
Some compounds cannot be taken orally b/c stomach acid destroys the active ingredient so sublingiual is good alternative

Question 10

capsules

Answer 10

2 ends can be pulled apart. Not used much anymore b/c they can be pulled apart and emptied then filled with bad things like guy who put cyanide in tylenol capsules
Some tablets look like capsules but are just compressed tablets

Question 11

solution

Answer 11

drug in solvent that is equally distributed through liquid; it is homogenized, unlike suspensions where it is not homogenized

Question 12

common dosage forms

Answer 12

tablets, transdermal patches, inhalers, suppositories, injections, creams, ointments, and lotions

Question 13

ointments

Answer 13

emulsions that have more oil than water; like vaseline

Question 14

creams

Answer 14

emuliant system like ointment, but have more water than oil

Question 15

lotion

Answer 15

emuliant system like cream, but even thinner (more water)

Question 16

steroid, same drug and strength in cream vs. ointment

Answer 16

will not have same efficacy. Chemical nature of drug may want to separate from ointment. Up to 10-fold difference in potency just by changing dosage form

Question 17

powders

Answer 17

add water to powder that contains medicine then administer. Many drugs have poor shelf life so this stores them and then can be used when necessary by adding water.

Question 18

route of administration of a drug follows the pattern of the drug formulation

Answer 18

ex. suppository preparations are only meant to be taken rectally; cannot be used in other ways

Question 19

some drugs are easier to formulate in any form we want, while others…

Answer 19

can only be made in one form and be effectively administered by that specific route

Question 20

oral dosage form

Answer 20

oral tablets and liquids are most common, convenient, and safe routes of admin
Disadvantages: relatively slow onset, inactivation by stomach acid, first pass inactivation, interaction with foods and adverse GI side effects

Question 21

Oral dosage form disadvantages

Answer 21

common GI side effects include nausea, vomiting, diarrhea, and anorexia (loss of appetite)
Liver recieves all portal blood after absorption into SI and has cells with granule enzymes that inactivate and change drugs (ex. nitroglycerin orally never reaches systemic b/c of 1PE; opioids are largely effects too so orally a high dose is needed so some can get through 1PE)

Question 22

oral tablets

Answer 22

dissolvable solids that usually can be scored down middle so it can be taken in half

Question 23

solutions

Answer 23

liquids which the mixture of ingredients remains dissolved no matter how long it sits
because of ease of preparation, if active ingredient can be dissolved in water then usually it is made into a solution

Question 24

caplets

Answer 24

powdered drug or gels suspended inside, but cannot be halved or broken like a capsule

Question 25

suspensions

Answer 25

liquids containing non-dissolved contents, some of which settle to bottom while on shelf; most antacids are suspensions that must be shaken before use

Question 26

Elixirs

Answer 26

sweet solutions in which active ingredient is dissolved in water (often with alcohol)

Question 27

Tinctures

Answer 27

very concentrated alcohol solutions; usually applied to skin

Question 28

sublingual

Answer 28

not swallowed, just placed under tongue to be absorbed by large BVs found there
only a few drugs can be given this way (most notably NTG)

Question 29

nasogastric

Answer 29

give through an NG tube; usually liquid drugs and nutrients given this way

Question 30

drugs are only approved in dosage form they are tested

Answer 30

can’t test a drug in tablet form and get it approved then sell it also as a cream

Question 31

gastrostomy tube

Answer 31

tube surgically placed directly into stomach or small intestines

Question 32

rectal suppositories

Answer 32

absorption is very quick and effective. Useful for very young or if they are vomiting.

Question 33

vaginal cream and suppositories

Answer 33

used for infections and irritations of vaginal tract; most are now OTC but used to be Rx.
Cream intravaginally is no different than oral medicines; both just apply medicine to a mucous membrane (often same cream will be used for mouth and vagina, just rebranded)

Question 34

topicals

Answer 34

Creams, ointments, eye drops, nasal sprays. Only certain drugs can be give this way; given at one location and it used to treat something in that specific location

Question 35

Eye drop tips

Answer 35

do not drop the drops near the nose or it will drain faster from the channel that drains the eye that is located on the nose side

Question 36

trans-dermal

Answer 36

different than topical because it is applied like a topical, but is absorbed trans-dermally and have systemic action, not just at application site. Ex. nicotine patches.
Steady blood levels can be achieved in some medications in patches applied to skin

Question 37

Transderm Scop

Answer 37

first transdermal medication that came out; scopolamine didn’t work great orally

Question 38

solutions can be provided by…

Answer 38

ampule: break top part off and draw out contents with a syringe
vile: different top than ampule. Small glass bottle containing liquid or powder. There is a rubber top that the needle can be placed through to absorb the solution

Question 39

inhalation

Answer 39

very effective way to admin aerosolized liquid medications and very fine powders. Achieves fast response.
Use metered dose inhaler (MDI) or nebulizer (changes liquid medication to mist so can be inhaled).
Second best way to give drugs besides IV, basically any water soluble drug given this way is just as good as IV

Question 40

Parenteral

Answer 40

anything other than enteral (oral or rectal), but usually means anything by injection

Question 41

enteral

Answer 41

admin of drug to stomach or intestines

Question 42

SC

Answer 42

subcutaneous: injection given just under skin, but above muscle layer; there are fewer BVs here so drug is absorbed more slowly

Question 43

drug expiry date

Answer 43

drug at this point must be within 5% of marketed strength, though some drugs can be used years past this date. Others, like tetracycline or other Rx medications, can turn toxic, but most OTCs are fine after.

Question 44

IV balloon bags

Answer 44

do not require gravity to drip drugs into systemic circulation b/c balloon shrinking provides force to supply drug into body
Allows patients who need IV to walk around and leave hospital and still have IV delivered

Question 45

IM

Answer 45

intramuscular: injection directly into muscle which have many BVs so drugs are absorbed quickly
Oral absorption is usually best route of absorption, but if person can’t then IM is usually given (parenterally)

Question 46

ED drugs

Answer 46

erectile dysfunction drugs used to given by intercavernous (into the corpus cavernosus) injection, but now oral drugs like viagra can be taken which are much less foreboding

Question 47

IV

Answer 47

intravenous: fastest parenteral injection. Effects are seen almost immediately, which can be dangerous if done incorrectly so only should be done with great care and expertise.

Question 48

intra-arterial

Answer 48

almost never done; directly into artery

Question 49

intra-articular

Answer 49

directly into joint

Question 50

intracardiac

Answer 50

done in movies, but not in real life

Question 51

intradermal

Answer 51

new influenza done this way; directly into skin

Question 52

intrathecal

Answer 52

into spinal space; done for spinal anesthesia or for placement of antibiotics for meningitis

Question 53

via umbilical artery or vein

Answer 53

commonly used in the neonatal ICU b/c after a few hours the opening closes in the newborn and cannot every be used again

Question 54

just 1 cc of local anesthetic given ___ could make the whole body go to sleep

Answer 54

intrathecal (directly to spinal cavity)

Question 55

topical admin leads to lowest blood levels unless…

Answer 55

designed for transdermal delivery which requires a special membrane and large drug reservoir

Question 56

how drug is formulated determines…

Answer 56

how it should be administered. Strongly frowned upon to give medication in dosage form different than specified, but if only option you have to do what you have to do.
Some drugs, like monoclonal antibodies, cannot be given in any method besides one (antibodies must be given by IV or will be destroyed)

Question 57

universally appropriate drug admin method

Answer 57

there is none. But IV is closest to being universal.

Question 58

Elixir could not be given if…

Answer 58

patient is taking Antabuse (disulfiram) b/c it inhibits detoxification of alcohol so violent reaction could occur

Question 59

suppository formulation versus oral

Answer 59

absorbed more quickly and reach higher blood levels, but are hard to find and not as cheap. Plus people don’t like to take them.