This document discusses topical drug delivery systems and methods for evaluating different topical dosage forms. It begins by defining the two basic types of topical delivery as external and internal. It then lists several advantages of topical drug delivery systems, such as avoiding first-pass metabolism and providing localized treatment. Potential disadvantages include skin irritation and poor drug permeability. The document describes common topical dosage forms like ointments, creams, emulsions, pastes, and gels. It provides details on evaluation methods for things like penetration rate, absorption, irritation effects, rheology, thermal stability, and drug content of different dosage forms. Evaluation methods for specific forms like powders, suspensions, aerosols, and suppositories are

1. Evaluation of
topical dosage
forms
Zohre jelodarian
School of pharmacy , Kermanshah University of Medical Sciences , Krmanshah , Iran

2. Topical delivery includes two
basic types of product:
1. External topicals that are
spread, sprayed, or otherwise
dispersed on to cutaneous
tissues to cover the affected
area.
2. Internal topicals that are
applied to the mucous
membrane orally, vaginally or
on anorectal tissues for local
activity.

3. Advantages of Topical Drug
Delivery Systems
Avoidance of first pass metabolism.
Convenient and easy to apply.
Avoidance of the risks and inconveniences of
intravenous therapy and of the varied conditions of
absorption, like pH changes, presence of enzymes,
gastric emptying time etc.
Achievement of efficacy with lower total daily
dosage of drug by continuous drug input.
Avoids fluctuation in drug levels, inter- and
intrapatient variations.

4.  Ability to easily terminate the medications, when
needed.
 A relatively large area of application in comparison
with buccal or nasal cavity
 Ability to deliver drug more selectively to a specific
site.
 Avoidance of gastro-intestinal incompatibility.
 Providing utilization of drugs with short biological
half-life, narrow therapeutic window.
 Improving physiological and pharmacological
response.
 Improve patient compliance.
 Provide suitability for self-medication.

5. Disadvantages of Topical Drug Delivery
Systems
• Skin irritation of contact dermatitis may occur
due to the drug and/or excipients.
• Poor permeability of some drugs through the s
kin.
• Possibility of allergenic reactions.
• Can be used only for drugs which require very
small plasma concentration for action
• Enzyme in epidermis may denature the drugs
• Drugs of larger particle size not easy
to absorb through the skin

6. Topical dosage
forms
Solid Liquid Semi solid
powder Lotion Ointment
Aerosol Liniment Cream
Plaster Solution Paste
Emulsion Gel
Suspension Jelly
Aerosol Suppository

7. The layers of skin

8. The layers of epidermis
o Stratum Germinativum
(Growing Layer)
o Malpighion Layer (pigment
Layer)
o Stratum Spinosum (Prickly
cell Layer)
o Stratum Granulosum
(Granular Layer)
o Stratum Lucidum
o Stratum Corneum (Horny
Layer)

9. Evaluation Of Topical Dosage Form
21-day cumulative
irritancy patch
test
Draize-shelanski
repeat-insult
patch test
Kligman
Evalution of patch “maximization”
test

10. Evaluation Of Topical Dosage Form
Penetration
Evaluation of
ointments
Rate of release of
medicaments
Absorption of
medicaments into
blood stream
Irritant effect

11. Evaluation Of Topical Dosage Form
Evaluation of
Rheology
cream
Sensitivity
Biological
testing

12. Evaluation Of Topical Dosage Form
Phase separation
Globule size
Evaluation of
emulsions Rheological
properties
Effect of thermal
stresses

13. Evaluation Of Topical Dosage Form
Abrasiveness
Evaluation of paste
Particle size
Cleansing property
Consistency
pH of the product
Foaming character
Limit test for arsenic and lead
Volatile matters and moisture
Effect of special ingredients

14. Evaluation Of Topical Dosage Form
Shade control and lighting
Pressure testing
Evaluation of powder
Breakage test
Flow property
Particle size and abrasiveness
Dispersion of color

15. Evaluation Of Topical Dosage Form
Evaluation Sedimentation
suspension volume
Rheologic
methods
Electrokinetic
techniques
Particle size
changes

16. Evaluation Of Topical Dosage Form
Flame projection
Flash point
Vapor pressure
Density
Moisture
Evaluation of aerosol Aerosol valve discharge rate
Spray patterns
Dosage with metered valves
Net contents
Foam stability
Particle size determination

17. Evaluation Of Topical Dosage Form
Antiseptic
property
Evaluation Determination of
of lotion alcohol content

18. Evaluation Of Topical Dosage Form
Drug content
Evaluation of
gel Homogeneity of drug
content
Measurement of pH
Viscosity
Spreadability
Extrudability

19. Brookfield viscometer(RVT)

21. Evaluation Of Topical Dosage Form
Evaluation of Melting range
suppository test
Dissolution test
Liquefaction or
softening time
test

22. Thanks for your
attention