|
Efficacy,
Safety and Convenience of Dosage Forms
|
|
Systemic
dosage forms |
| |
Oral |
|
(mixture,
syrup, tablet [coated, slow-release], powder, capsule) |
| |
sublingual
|
|
(tablet,
aerosol) |
| |
rectal |
|
(suppository,
rectiol) |
| |
inhalation |
|
(gases,
vapour) |
| |
injections
|
|
(subcutaneous,
intramuscular, intravenous, infusion) |
| |
Local
dosage forms |
| |
skin |
|
(ointment,
cream, lotion, paste) |
| |
sense organ |
|
(eye drops/ointment,
ear drops, nose drops) |
| |
oral/local
|
|
(tablets,
mixture) |
| |
rectal/local
|
|
(suppository,
enema) |
| |
vaginal
|
|
(tablet,
ovule, cream) |
| |
inhalation/local |
|
(aerosol,
powder) |
| |
Oral
forms |
| |
efficacy
|
: |
(-)
uncertain absorption and first-pass metabolism, (+) gradual effects
(that is a ,
drug may be metabolised before it can be measured in the systemic
circulation - one of the causes of low oral bio-availability. For
more information see: http://www.merck.com/pubs/mmanual/section22/chapter298/298c.htm
). |
| |
|
|
| |
|
|
| |
safety |
: |
(-) low
peak values, uncertain absorption, gastric irritation |
| |
convenience
|
: |
(-) handling
(children, elderly) |
|
Sublingual
tablets and aerosols |
| |
efficacy |
: |
(+) act
rapidly, no first-pass metabolism |
| |
safety |
: |
(-) easy
overdose |
| |
convenience
|
: |
(-) aerosol
difficult to handle, (+) tablets easy to use |
|
Rectal
preparations |
| |
efficacy
|
: |
(-) uncertain
absorption, (+) no first-pass metabolism, rectal fast effect
|
| |
safety |
: |
(-) local
irritation |
| |
convenience |
: |
(+) in case
of nausea, vomiting and problems with swallowing |
| |
Inhalation
gases and vapours |
| |
efficacy
|
: |
(+) fast
effect |
| |
safety |
: |
(-) local
irritation |
| |
convenience |
: |
(-) need
handling by trained staff |
| |
Injections
|
| |
efficacy
|
: |
(+) fast
effect, no first-pass metabolism, accurate dosage possible |
| |
safety |
: |
(-) overdose
possible, sterility maybe a problem |
| |
convenience |
: |
(-) painful,
need trained staff, more costly than oral forms |
| |
Topical
preparations |
| |
efficacy |
: |
(+)
high concentrations possible, limited systemic penetration |
| |
safety
|
: |
(-)
sensitization in case of antibiotics, (+) few side effects
|
| |
convenience
|
:
|
(-)
some vaginal forms difficult to handle |
| |
Source:
Guide
to Good Prescribing,
WHO Action Programme on Essential Drugs, Geneva, 1995. |
|
|
Suppositories
are solid bullet-shaped drug forms which can be easily inserted into the
rectum; and when these drug forms are available for insertion into the
vagina, they are called pessaries. They both contain a drug and
an inactive substance which is derived from vegetable oil or cocoa butter.
The active ingredients are released slowly as the suppository or pessary
dissolves at body temperature.
Drops
for eyes, ears and nose are drug solutions administered by means of a
dropper.
Nasal
Spray contains a solution of a drug in water administered in the
nose by means of a dropper or spray.
Inhalers
are drugs in solution or suspension form which are then released under
pressure. The aerosol inhalers function by means of a valve mechanism
which ensures delivery of the recommended dosage. It contains a mouth
piece and is used for respiratory conditions.
Evaluation
of Drug Profiles
The drug
profiles in this book in Section 2 give detailed information on 51 individual
drugs. The drugs have been so selected that they cover all the main drug
classes which are widely used. When a certain drug-class comprises a number
of different drugs, only the ones that are most commonly used have been
included in this book.
The drug profiles are
aimed at providing information and guidance to the lay person. Information
on 107 other drugs has been included in tabular form in Section 3.
Each drug profile is
presented in the same way, using standard headings in a uniform sequence.
To help the reader understand the information, each heading of the drug
profile is explained in detail.
|