Transcript Chapter 2 Law and Ethics of Pharmacy Teresa Hopper

Chapter 5
Dosage Forms, Abbreviations,
and Routes of Administration
Copyright © 2004 by Elsevier Inc. All rights reserved.
Introduction
• For a technician to become proficient,
it is necessary to interpret orders
correctly
• Many doctors’ handwriting is referred
to as “chicken scratch” and it is the
responsibility of the pharmacy to
interpret and clarify orders if necessary
• Many abbreviations used in prescribing
medication look very much alike
Copyright © 2004 by Elsevier Inc. All rights reserved.
Where Do Pharmacy
Abbreviations Originate?
• Terminology in pharmacy and
medicine comes from the Latin
and Greek languages
• Because pharmacy began in Europe,
most of the abbreviations have their
origins in a foreign language
• Latin and Greek serve as the universal
language that all medical personnel
can understand
Copyright © 2004 by Elsevier Inc. All rights reserved.
Interpreting Doctors’ Orders
• It is very important for the pharmacy
staff to interpret doctors’ orders correctly
• When writing out the various abbreviations,
be sure to write as neatly as possible
because other technicians and pharmacists
will be reading your handwriting
• Technicians must learn all of the dosage
forms and abbreviations to decipher
doctors’ orders
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Dosage Forms
• A dosage form refers to the package
or container of which the drug has
taken the shape
• For example, it may be a tablet or
a capsule
• There is more than one type of tablet
or capsule
• Tablets come in a wide variety of
shapes and sizes
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Dosage Forms
• Tablets can be scored or unscored
and coated or uncoated
• Much of what determines the dosage
form of a medication is determined
by the drug’s effectiveness
• Manufacturers prepare certain
medications with the ability to
release the active ingredient
over an extended period
Copyright © 2004 by Elsevier Inc. All rights reserved.
A. Unscored tablet
B. Scored tablet
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Dosage Forms
• This allows the patient to take the
medication less often, which
increases compliance
• Three major categories of dosage forms:
– Solids
– Liquids
– Semisolids
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Dosage Forms
• Solids
• Solid agents can be contained in
various packages and administered by
almost all routes except parenterally
• Most tablets contain fillers (inert
substances–no active ingredient),
sugar coatings, and certain additives
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Dosage Forms
• Tablets are made to be administered
sublingually (sl) or vaginally
• Tablets can be scored to allow for
dosage to be cut in half
• Chewable tablets are convenient
for persons who have difficulty
swallowing and for children
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Dosage Forms
• Tablets can be enteric coated (EC)
to protect the drug through the acidic
environment of the stomach or to
delay release of the drug
• Extended-release–types are made to
control the amount of drug distributed
over a set time
Copyright © 2004 by Elsevier Inc. All rights reserved.
Plain tablets
Scored tablets
Copyright © 2004 by Elsevier Inc. All rights reserved.
Enteric-coated
tablets
Capsules and Caplets
• Capsule and caplet dosage forms
are closely related to tablets
• Capsules can have either a hard or
soft outer shell
• Hard capsules are composed of sugar,
gelatin, and water
• Pulvule–type of capsule that is shaped
differently for identification purposes
Copyright © 2004 by Elsevier Inc. All rights reserved.
Capsules and Caplets
• Spansules–can be pulled apart to
sprinkle the medication onto food
for children
• The main difference between capsules
and caplets is that capsules can be
pulled apart
Copyright © 2004 by Elsevier Inc. All rights reserved.
Types of Capsules
Capsules
Extended-release
capsules
Copyright © 2004 by Elsevier Inc. All rights reserved.
Lozenges/Troches
• These are other forms of tablets that
are not meant to be swallowed but to
dissolve in the mouth, which releases
the medication more slowly; similar
to hard candy
• Cough drops
• Troches are larger than normal-sized
tablets and are flat; chalky consistency
Copyright © 2004 by Elsevier Inc. All rights reserved.
Implants
• A special type of capsule can be
implanted under the skin and left
in place for up to 5 years
• Contraceptives containing progestin
• Medication is released in a stair-step
method
Copyright © 2004 by Elsevier Inc. All rights reserved.
Patches
• Solid pieces of material that hold
a specific amount of medication to
be released into the skin over time
• Easily administered and eliminate
a possible upset stomach
• Uses: Angina-Nitroglycerin;
chronic pain- Duragesic
• Motion sickness-Scopolamine
Copyright © 2004 by Elsevier Inc. All rights reserved.
Liquids
• Composed of various solutions
• Can be administered by all routes
• Syrups–sugar-based solutions that
have medications dissolved in them,
which improves the taste of the drug.
They tend to be thicker than water
Copyright © 2004 by Elsevier Inc. All rights reserved.
Liquids
• Elixirs–agents that contain dissolved
medication in either an alcohol base
or water and alcohol (hydroalcoholic)
base
• Alcohol usually covers up the bad
taste of the drug
• Elixirs have the same consistency
as water
Copyright © 2004 by Elsevier Inc. All rights reserved.
Sprays
• Sprays are composed of various bases
as alcohol or water in a pump-type
dispenser
• Nasal decongestants or sunscreens
• Nitroglycerin translingual spray that
is used under the tongue for relief of
anginal pain
Copyright © 2004 by Elsevier Inc. All rights reserved.
Inhalants and Aerosols
• Inhaler agents come in a variety of
forms but all must be easily inhaled
into the lungs
• Common devices available OTC are
vaporizers and humidifiers
• Respiratory therapists use nebulizers
to give breathing treatments to hospital
patients
• Patients can also be trained to use
nebulizers at home
Copyright © 2004 by Elsevier Inc. All rights reserved.
Inhalants and Aerosols
• Anesthetics come in solutions that
are inhaled and administered during
surgery by an anesthesiologist
• Prescribed inhalants contain drugs
that treat asthma and allergies
• Metered dose inhalers (MDIs)
dispense a specific amount of
drug with each puff or inhalation
Copyright © 2004 by Elsevier Inc. All rights reserved.
Emulsions
• The mixture of water and oil when
used with an emulsifier binds the
two together
• Oil can have water as a base
• Water is contained in an oil base
• Most emulsions are used topically. Some
are used parenterally, such as lipids
(fats) in nutritional parenteral feedings
Copyright © 2004 by Elsevier Inc. All rights reserved.
Suspensions
• These are liquids that have very small,
solid particles suspended in the base
solution
• They can be used orally by children
and seniors
• Suspensions have a “shake well”
sticker and a date of expiration
Copyright © 2004 by Elsevier Inc. All rights reserved.
Enemas
• Enemas may be administered for
two different reasons–retention
or evacuation
• They can be used to deliver medication
to the body, bypassing the stomach
while being absorbed
• Most common use is to evacuate the
lower intestine to prepare for surgeries
or for women in labor
Copyright © 2004 by Elsevier Inc. All rights reserved.
Semisolids
• Semisolids contain both liquids
and solids
• They are meant for topical application
• Creams–have medications in a base
that is part oil and part water and for
topical use
• Lotions are thinner than creams
because their base contains more
water
Copyright © 2004 by Elsevier Inc. All rights reserved.
Semisolids
• Ointments contain medication in a
glycol or oil base; they cover the
skin surface and keep out moisture
• Gels contain medication in a very
viscous (thick) liquid that easily
penetrates the skin
• Pastes contain a lesser amount of liquid
base than solids. They are able to absorb
skin secretions unlike other topical
agents
Copyright © 2004 by Elsevier Inc. All rights reserved.
Suppositories
• Can be used both rectally and vaginally
• Rectal suppositories bypass the
stomach, which is important if the
patient has nausea and vomiting
• Vaginal suppositories are used mainly
to treat vaginal infections
Copyright © 2004 by Elsevier Inc. All rights reserved.
Powders
• Powders are solids, yet they can be
packaged in some forms that allow
them to be sprayed similar to liquid
dosage forms
• One of the main uses is to decrease
the amount of wetness of an area
• Antifungal foot agents
• They can also be spread over a wide area
Copyright © 2004 by Elsevier Inc. All rights reserved.
Routes of Administration
• By mouth or oral medications are
very convenient, do not need to be
measured, less expensive, systemic,
and safe
• The downside is that they do not
work as quickly as parenterals
• Some drugs cannot be taken orally
because they are not as effective
Copyright © 2004 by Elsevier Inc. All rights reserved.
Sublingual and Buccal Agents
• Nitroglycerin is the most commonly
used sublingual tablet that treats
anginal attacks
• Buccal agents are placed between the
gum and cheek where the medication
penetrates the mouth lining and then
enters the bloodstream
Copyright © 2004 by Elsevier Inc. All rights reserved.
Rectal
• Rectal (R) agents are used in a person who
is vomiting and cannot take oral medications
• To reduce inflammation, either ointments or
creams can be used in addition to
suppositories
• They work on a specific site and not
systemically
• Downside–they are uncomfortable and the
actual amount of drug absorbed is
unpredictable
Copyright © 2004 by Elsevier Inc. All rights reserved.
Capsule Sizes
• Capsules vary in size, color,
transparency, and identifying marks
• The larger half of the capsule is known
as the body and the smaller half is
known as the cap
• Not all capsules are meant to be
swallowed; specific dosages of
medications can be sprinkled onto
food or into liquids
Copyright © 2004 by Elsevier Inc. All rights reserved.
Topical
• Topical (TOP) preparations effects range
from systemic to localized for rashes
• There are agents to fight skin infections,
inflammation, and UV rays of the sun
• They work at the site of action and
systemically
• An advantage is easy application
• A downside is that they may cause
a reaction
Copyright © 2004 by Elsevier Inc. All rights reserved.
Parenteral: Intravenous, Intravenous
Piggyback, Intramuscular, Subcutaneous
• Parenteral comes from the Greek and means
“side of intestine” or “outside of intestine”
• The most common parenteral medications
are given IV, IM, or SC
• Very small gauge needles are used, and the
length depend on the site being injected
• Benefits–speed of action
Copyright © 2004 by Elsevier Inc. All rights reserved.
Parenteral: Intravenous, Intravenous
Piggyback, Intramuscular, Subcutaneous
• Parenteral drugs work within a few
minutes
• Important for emergency situations,
for those who are combative, or for
those who are unable to swallow
• A disadvantage is the increased risk
of infection
Copyright © 2004 by Elsevier Inc. All rights reserved.
Parenteral: Intravenous, Intravenous
Piggyback, Intramuscular, Subcutaneous
• Injections are more expensive and
require preparation and administration
by trained personnel
• Another downside is that once a drug
is injected there is little time to alter
its course if an allergic reaction takes
place or too much drug is given
Copyright © 2004 by Elsevier Inc. All rights reserved.
Eye, Ear, Nose
• Doctors often use eye solutions to treat
ear conditions, but ear solutions cannot
be used to treat eye conditions because
the eye is sterile
• All eye agents are sterile
• Otic preparations are not necessarily
sterile because they treat the ear canal
and do not penetrate a sterile environment
Copyright © 2004 by Elsevier Inc. All rights reserved.
Eye, Ear, Nose
• All ophthalmics need to be kept sterile
• For the eye, ear, and nose there are
different types of agents, including
ointments, solutions, and suspensions
• Most ear treatments are for clearing
up infections or cleaning out ear wax
buildup
Copyright © 2004 by Elsevier Inc. All rights reserved.
Eye, Ear, Nose
• Most nasal sprays are used to treat
colds and allergies
• Eye treatments are for infections,
inflammation, and glaucoma
• These dosage forms work on the
specific site rather than the whole
body
Copyright © 2004 by Elsevier Inc. All rights reserved.
Eye, Ear, Nose
• A main disadvantage of solutions
for the eye, if not kept sterile, is that
they can introduce bacteria into the
area being treated
• Ophthalmics do not last as long as
other treatments because of the
blinking of the eye and tearing
• Ointments make it hard to see clearly
Copyright © 2004 by Elsevier Inc. All rights reserved.
Inhalants
• Inhalants (INH) are used to treat
lung diseases
• Dosage forms are limited but very
effective if used properly
• MDIs are used for asthma, bronchitis,
or emphysema
• Corticosteroids are also available
in MDIs for more chronic conditions
Copyright © 2004 by Elsevier Inc. All rights reserved.
Inhalants
• Onset of action is very quick
• Most aerosols come in handheld
units and are very convenient
• The downside is that, if not used
properly, little if any of the drug is able
to get into the lungs
Copyright © 2004 by Elsevier Inc. All rights reserved.
Miscellaneous Routes
• Vaginal or uretheral dosage forms–
suppositories, ointments, foams,
and gels
• They are used for treatments of
infections and inflammation; vaginal
foams are used as a contraceptive
• Advantages are they bypass a systemic
effect and affect a specific site but are
not easily applied and are uncomfortable
Copyright © 2004 by Elsevier Inc. All rights reserved.
Other Considerations:
Form and Function
• Dosage forms are created based on
the results from many clinical trials
that delve into the pharmacokinetics
of the medication or the function of
the drug in experiments
Copyright © 2004 by Elsevier Inc. All rights reserved.
Pharmacokinetics
• Represent many different components
concerning the actions of a drug
• Considerations such as:
– Levels of the drug throughout the
blood and tissues
– Absorption or movement of the
drug throughout the body
– Overall distribution
Copyright © 2004 by Elsevier Inc. All rights reserved.
Pharmacokinetics
• Metabolism
• Excretion of the drug
• Reaction of the drugs with other drugs
• Patient compliance
• Life of the drug that includes
bioavailability, half-life, bioequivalence,
and excretion
Copyright © 2004 by Elsevier Inc. All rights reserved.
Absorption
• Medications are made to get through
natural body barriers, such as the
skin, stomach, intestines, blood-brain
barrier, and other membranous tissues
• How well the drug passes through these
barriers is the one factor that determines
its ultimate effectiveness
Copyright © 2004 by Elsevier Inc. All rights reserved.
Absorption
• Important chemicals and drugs are
able to pass a lock and key mechanism
by latching onto receptor sites that
allow the chemical or drug to pass
into the organ to reach the final
site of action intended for the drug
Copyright © 2004 by Elsevier Inc. All rights reserved.
Distribution
• After the absorption of a medication,
it is distributed throughout the body
from the bloodstream into tissues,
membranes, and ultimately organs
of the body
• The distribution of a drug throughout
the body is not necessarily equal
throughout the whole body
Copyright © 2004 by Elsevier Inc. All rights reserved.
Metabolism
• Most metabolism takes place
in the liver
• Metabolism changes the chemical
structure of the original drug
• There are different influences that can
alter metabolism such as age, gender,
genetics, diet, and other chemicals
digested
Copyright © 2004 by Elsevier Inc. All rights reserved.
Excretion
• Excretion is the last phase of a drug’s
life in the body
• There are many ways a drug can
be excreted from the body: via the
kidneys, feces, exhalation, sweat
glands, breast milk
• Urination and bowel movements
are the most common methods
of excretion
Copyright © 2004 by Elsevier Inc. All rights reserved.
Bioavailability
• This is the rate at which the drug
makes it to its destination and is
available to the site of action for
which it was intended
• Many drugs travel into the liver
before they have a chance to be
absorbed into the whole system.
• Known as the “first pass effect”
Copyright © 2004 by Elsevier Inc. All rights reserved.
Half-Life
• Refers to the measurement of the time
it takes the body to break down and
excrete one half of the drug
• This is an important factor in the
creation of drugs for it tells the
manufacturer how long it takes the
body to rid itself of the drug
Copyright © 2004 by Elsevier Inc. All rights reserved.
Bioequivalence
• This is the comparison between drugs
either from different manufacturers
or in the same company but from
different batches of a drug
• Generic drug manufacturers strive
to achieve the same equivalence
as brand name manufacturers for
competition
Copyright © 2004 by Elsevier Inc. All rights reserved.
The Use of Additives
• All medications are prepared with
some sort of additive
• These include coloring, flavorings,
fillers, and preservatives
• Other types include those that
increase the dispersing of the
drug once it reaches the intestines
and others that release the medication
over a longer period of time
Copyright © 2004 by Elsevier Inc. All rights reserved.
Manufactured Products
• All types of dosage forms must be
made and approved by the Food and
Drug Administration (FDA)
Copyright © 2004 by Elsevier Inc. All rights reserved.
Large-volume IV
IVPB
Copyright © 2004 by Elsevier Inc. All rights reserved.
Miscellaneous Agents and Devices
• Ocular inserts–lenses inserted into
the eye that release a continuous
amount of drug over time
• Injectable Forms–long-acting for birth
control, antipsychotic episodes, and
steroids
Copyright © 2004 by Elsevier Inc. All rights reserved.
Packaging and Storage
Requirements
• Medications are packaged according
to manufacturers’ specifications to
ensure effectiveness and shelf life
of the drug
• All medications have a package insert
that describes the storage and stability
of the drug
Copyright © 2004 by Elsevier Inc. All rights reserved.