2. Pharmaceutics
• Pharmaceutics is the science of dosage form design.
• There are many chemicals with known
pharmacological properties but a raw chemical is of
no use to a patient.
• Pharmaceutics deals with the formulation of a pure
drug substance into a dosage form.
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3. Active Drug Substance
• (Active pharmaceutical ingredient - API)
• Chemical compound with pharmacological (or
other direct effect ) intended for use in
diagnosis, treatment or prophylaxis of diseases.
• International non-proprietary names (INN,
generic names)
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4. Direct clinical use of the active drug substances „as
they are“ is rare due to a number of good reasons:
• API handling can be difficult or impossible (e.g., low mg and g
doses)
• Accurate drug dosing can be difficult or impossible
• API administration can be impractical, unfeasible or not according
to the therapeutic aims
• Some API can benefit from reducing the exposure to the
environmental factors (light, moisture…), or they need to be
chemically stabilised due to the inherent chemical instability
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5. Direct clinical use of the active drug substances „as
they are“ is rare due to a number of good reasons:
• API can be degraded at the site of administration (e.g., low pH in
stomach)
• API may cause local irritations or injury when they are present at
high concentrations at the site of administration
• API can have unpleasant organoleptic qualities (taste, smell –
compliance!)
• Administration of active substance would mean to have no chance
for modification (improvement) of its PK profile
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6. From drug substance to pharmaceutical
preparation
• Besides the choice of the active drug substance, you
need to also make a responsible decision regarding
the route of administration and the DOSAGE
FORM (drug delivery system) – wrong choice can
cause failure of therapy
• You should also be able to handle and administer the
drug properly or advise the patient about it – wrong
use can cause failure of therapy
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7. Excipients
• Excipients (inactive pharmaceutical ingredients)
• Its selection depends on technological,
biopharmaceutical and/or stability
reasons.
• Diluents/fillers, binders, lubricants,
coatings, preservatives, colorants and
flavouring agents
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8. Pharmaceutical dosage form
• Pharmaceutical dosage form
• Determines the physical form of the final
pharmaceutical preparation
• Is a drug delivery system which is formed by
technological processing (drug formulation)
• Must reflect therapeutic intentions, route of
administrations, dosing etc.
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9. Pharmaceutical preparation (PP)
• Pharmaceutical preparation (PP)
• particular pharmaceutical product containing active and inactive
pharmaceutical ingredients formulated into the particular dosage form.
• Packed and labelled appropriately
• Two major types of PP according the origin:
• Manufactured in large scales by pharmaceutical
industry (original and generic preparations)
• Compounded individually in compounding
pharmacies
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10. 1- Pharmaceutical preparations
manufactured by pharmaceutical industry
1.1- Original pharmaceutical preparations
• undergo full and very extensive pharmacological/
toxicological and pharmaceutical pre-clinical and
clinical development and evaluation
• particularly important is the proof of effectiveness
and safety
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11. - Can be released after the expiration of the patent protection of the original
preparation
• The approval for clinical use is easier due to the prior experience with the
original preparation
• Must be pharmaceutically equivalent: same API, dose, pharmaceutical
dosage form and the same route of administration as in original preparation
• Must be clinically bioequivalent: i.e. it must be of very close PK profile as
original preparation. PK parameters (Cmax, tmax, AUC) are within 80-125
% range as compared with the original preparation.
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1.2- Generic pharmaceutical preparations
(„authorised copies of original preparations“)
12. 2- Pharmaceutical preparations
compounded individually
• These PP are compounded individually for a particular patient according
to the physician's prescription in a pharmacy licensed for compounding
• In contrast to the past, they are used rather rarely and mostly in specific
situations
• It is highly advisable that whenever the particular suitable PP is approved
and commercially available it should be preferred over the compounding
• The major disadvantage is the lack of standardization (it is always a
„single-patient batch“), unavailability of rigorous QC testing and the
appropriate clinical evaluation.
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13. The individually compounded PP
can be a justified choice when:
• The drug in a particular dosage form is not commercially
available on the market
• The extraordinary low or high dose is needed (young children,
elderly people, special situations – e.g., intoxications). In this
case right dosage strength need not be readily commercially
available for every patient
• The patient suffers from the allergy on a specific excipients
(e.g., lactose – a filler, some colorizing/flavouring or
antimicrobial agents - parabens) or another drug appearing in
the PP
• Patient is unable to use a PP in its commercially available
dosage form (e.g., children, elderly)
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14. Classification of pharmaceutical dosage forms
according to physical properties
• Gaseous dosage forms
• Liquid dosage forms
• Semisolid dosage forms
• Solid dosage forms
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15. Gases
• Medicinal gases, inhalation/volatile anaesthetics
(vaporised before administration by inhalation)
• Aerodispersions of solid particles (e.g., antiasthmatic
inhalations) or liquid particles (antiasthmatic
inhalations or sprays)
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16. Liquids
• Solutions – one homogenous phase, prepared by dissolving one or more solutes in a
solvent
• Emulsions
• a dispersion system consisting of two immiscible liquids
• o/w or w/o
• cloudy appearance
• Suspensions
• A dispersion system where solid particles (dispersed phase) are dispersed in liquid
phase (dispersion medium)
• According to the size of dispersed particles (1 nm- 0,5 mm) a molecular, colloidal and
coarse dispersions can be distinguished
• May require shaking before administration
• Not intended for systemic administration of drugs with high potency
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17. Semisolid dosage forms
1- Unshaped (without specific physical shape)
• Gels -A semisolid systems in which a liquid phase is constrained
within a 3D cross-linked matrix.
• Creams – semisolid emulsion systems (o/w, w/o) containing
more than 10% of water.
•o/w creams - more comfortable and cosmetically acceptable
as they are less greasy and more easily water washable
•w/o creams – accommodate and release better lipophilic
API, moisturizing, Cold creams 1
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18. Semisolid dosage forms
1- Unshaped (without specific physical shape)
• Ointments – semisolid dosage forms with the oleaginous
(hydrocarbon), water-soluble or emulsifying base
•Oleaginous (hydrocabon) base: Petrolatum (Vaseline –
white, yellow)
•Water-soluble base: Polyethylenglycol (PEG)- ointment –
syn. macrogol ointments
• Pastes – semisolid dispersion system, where a solid particles
(> 25%, e.g. ZnO) are dispersed in ointments – mostly
oleaginous (Petrolatum) 1
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19. Semisolid dosage forms
2- Shaped
• Suppositories (for rectal administration)
•different shapes
•Melting/dissolving at body temperature
•Oleaginous (cacao butter, adeps neutralis)
or aqueous (PEGs, glycerinated gelatine)
• Pessaries (vaginal suppositories)
•Similar as above, PEGs or glycerinated
gelatine are often used as base.
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20. Solid Dosage Forms
• Unshaped (without specific shape)
- powders for external/internal use
• Shaped
- Tablets
- Capsules
- Implantates (Sterile disks inserted surgically into body tissues
and designed to release drug(s) over extended period of time)
- Transdermal patches
- Lozenges (consists of sugar and gum to medicate the mouth and
throate)
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21. Classification of pharmaceutical dosage forms according
to the route of administration
• A drug’s route refers to how it is to be administered. Some drugs have multiple
routes with which they can be administered, with the correct route determined
by the medication’s action.
• for systemic administration
• Peroral (p.o)
• Sublingual (S.L) absorption under the tongue through the mucous •
membranes.
• buccal. absorption into the mucous membranes between the cheeks •
and gums.
• Rectal absorption into the bloodstream via the rectum
• Vaginal – absorption into the bloodstream via the vagina
• Parenteral
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22. • Transdermal adhesive patches transfer a drug through
• the skin; these commonly include medications for
motion sickness, angina pectoris, menopausal
symptoms, smoking cessation, and contraception.
• Inhalation Inhalation – the breathing in of sprays and
aerosols through the • mouth or nose.
• Implantation – implantable devices placed beneath the
skin near • blood vessels that lie below; may be used to
treat conditions such as cancer and diabetes, or for
contraception; greater doses with fewer adverse eff
ects than by systemic routes can be delivered
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23. • Topical- direct application to the skin. Certain
administrations of • eye or ear medicines (liquid
drops) may be referred to as “instillation,” though
these are in fact topical routes.
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24. • Most injected medications reach the systemic
circulation rapidly and quickly become eff ective, as
do sublingual medications (such as nitroglycerin).
Oral medications act more slowly because they must
fi rst be dissolved in the stomach and then absorbed
into the bloodstream. Suppositories are absorbed
more slowly than injected and sublingual
medications.
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25. • A patient’s physical condition, emotional state, and
level of consciousness are all considered when
selecting the proper route of administration. Drug
characteristics are also important to know and
understand. For example, insulin is usually given by
injection because it is (in most formulations)
destroyed by digestive enzymes, prohibiting oral
administration. Insulin is also available as a nasal
spray.
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26. • The most frequently used routes of administration
are oral and parenteral routes. It should be noted that
while the term parenteral actually means “by means
other than the digestive tract,” it is commonly
thought of as being defined by the term “injectable.”
Parenteral administration is associated with all forms
of a drug administered by a syringe, needle, or
catheter (including intramuscular, subcutaneous, and
intravenous administration).
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