This document discusses iontophoresis, which is a non-invasive technique for transdermal drug delivery using electricity. It works by using an electric current to transfer ions across the skin layers. The summary is: Iontophoresis is a painless, sterile technique that uses a small electric current to enhance delivery of ionized drugs through the skin. It works by using electrode placement and electric charge to drive positively or negatively charged drug ions into the body. The document discusses the principles, advantages, complications, mechanisms, equipment, and factors that influence iontophoresis drug delivery.

1. IONTOPHORESIS: TRANSDERMAL
DRUG DELIVERY
Guided by,
Professor Kurian Varghese &
Asst.Professor Dinu Thomas
Submitted by,
Amrith Vijay V L
S7 EEE
Rollno-8
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2. CCOONNTTEENNTTSS
 INTRODUCTION
 PRINCIPLES OF IONTOPHORESIS
 ADVANTAGES OF IONTOPHORESIS
 COMPLICATIONS IN IONTOPHORESIS
 IONTOPHORESIS DIAGRAM
 THREE MECHANISMS OF IONTOPHORESIS
 IONTOPHORETIC GENERATOR
 TREATMENT DURATION & PRECAUTION
 CONCLUSION
 REFERENCES
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3. Introduction
• The term IONTOPHORESIS simply defined as
ion transfer (ionto= ion & phoresis=transfer).
• It is a Painless, Sterile, Noninvasive Technique
for injecting medicine to the body by the
influence of electricity.
• Iontophoresis is well classified for use in
transdermal drug delivery.
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4. Principles of Iontophoresis
• Electrode placement is dependent on the electric charge of the
ion which you are trying to deliver into the tissue.
• A positive ion will be delivered from the positive electrode
and a negative ion will be delivered by the negative electrode.
• Electrical energy assists the movement of ions across the
stratum corneum according to the basic electrical principle
“like charges repel each other and opposite charges attract
each other.” So iontophoresis is done with the help of
electrostatic repulsion.
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5. Advantages of Iontophoresis
• Painless technique if properly done.
• Provides option for patients unable to receive
injections.
• Reduced risk of infection due to non-invasive nature.
•Medications delivered directly to the treatment site.
• Minimizes potential for tissue trauma from an
injection.
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6. Complications in iontophoresis
• Electric shocks may cause if excessive current
density occurs & usually results in pain.
• The high current density and time of application
would generate extreme pH, resulting in a
chemical burn.
• Iontophoresis cannot be done to patients with
cardiac pacemakers.
• Ionic form of drug in sufficient concentration is
necessary for iontophoretic delivery.
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7. IONTOPHORESIS DIAGRAM
Figure showing transdermal drug delivery by iontophoresis
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8. Iontophoresis enhances transdermal drug delivery
by three mechanisms
(a) Ion-electric field interaction provides an additional force
that drives ions through the skin.
(b) The flow of electric current increases the permeability
of the skin.
(c) Electro-osmosis produces bulk motion of solvent that
carries ions or neutral species with the solvent stream.
Electro-osmotic flow occurs in a variety of membranes and
is in the same direction as the flow of counter-ions. It may
assist or hinder drug transport.
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9. Components needed for effective iontophoresis
delivery
• Power source for generating controlled direct
current.
• Electrodes that contain and disperse the drug.
• Negatively or positively charged aqueous
medication.
• A localized treatment site.
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10. Movement of Ions In Tissue
Higher current intensities necessary to create ion movement in
areas where skin and fat layers are thick, further increasing
chance of burns around negative electrode.
Sweat ducts are primary paths by which ions move through
the skin.
Once the ions pass through skin they recombine with existing
ions and free radicals in the blood thus forming the necessary
new compounds for favorable therapeutic interactions.
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11. Iontophoresis Generator
¨Produce continuous
direct
current in the order as per
the requirement.
¨Assures unidirectional
flow
of ions.
¨It also consist of a timer
for regulating the supply
of current.
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12. ¨Intensity control
• 1 to 5 mA
• Constant voltage
output that adjusts to
normal variations in
tissue impedance thus
reducing the likelihood
of burns.
• Automatic shutdown if
skin impedance
reduces to preset limit.
¨Adjustable Timer for
giving the duration of
treatment
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13. Current Intensity
• CI can be found out by
Maximum current(mA)=
Maximum Safe Current Density(mA/cm2) x Electrode Area(cm2)
• Recommended current intensity used for iontophoresis ranges
between 3-5 mA
• Low amperage currents appear to be more effective as a driving
force than currents with higher intensities (16 to 512μA)
• The frequency of current should be in the range of 500 Hz to
avoid shock hazards
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14. Treatment Duration
Treatment duration ranges between 10-20 minutes with
15 minutes being an average.
Patient should be comfortable with no reported or visible
signs of pain or burning.
Check skin every 3-5 minutes looking for signs of skin
irritation.
Decrease intensity during treatment to accommodate
decrease in skin impedance to avoid pain or burning.
Usage of pulsed DC can be reduce the duration of
treatment 14

15. Treatment Precautions
¨Uses the most appropriate ions to accomplish the
treatment goal
¨Uses appropriate treatment parameters and
equipment set-up
¨Don’t use two chemicals under the same electrode
even if the they are of same polarity
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16. Electrodes of iontophoresis
Active pad- This electrode have
a small chamber covered by a
semipermeable membrane into
which ionized solution may be
injected.
Dispersive pad- Also known as
Inactive pad. Dispersive pad
should be larger than active pad
to reduce the current density
leading to reduction of irritation
The polarity of these electrode
depends on the characterictics of
drugs and these electrodes self
adheres to the skin.
Active pad
Dispersive pad
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17. Iontopatch
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18. Electrodes Material
The electrode materials used for iontophoretic delivery are
to be harmless to the body and sufficiently flexible to apply
closely to the body surface.
The most common electrodes used for iontophoretic drug
delivery are
 Aluminum foil
 Platinum and
 Silver/Silverchloride
A better choice of electrode is silver/silver chloride
because it minimizes electrolysis of water during drug
delivery.
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19. Electrode Preparation
To ensure maximum contact of
electrodes skin should be
shaved and cleaned prior to
attachment of the electrodes.
Do not excessively abrade
skin during cleaning since
damaged skin has lowered
resistance to current and a
burn might occur more
easily.
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20. • Attach self-adhering
active electrode to skin.
• Inject ionized solution
into the chamber.
• Attach self-adhering
inactive electrode to
the skin and attach lead
wires from generator to
each.
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21. Electrode Placement
• Size and shape of electrodes
can cause variation in
current density
(smaller = higher density)
• Inactive electrodes should
be separated by a distance
atleast the diameter of
active electrode
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22. Factors Affecting Iontophoretic Delivery of the Drug
 Operational Factors
I. Composition of formulation:
• Concentration of drug solution
• pH of donor solution
• Ionic strength
• Presence of co-ions
II. Physicochemical properties of the
permeant:
• Molecular size & Molecular weight
• Charge
• Polarity
III. Experimental conditions:
• Current density
• Duration of treatment
• Electrode material
• Polarity of electrodes
 Biological Factors
• Regional blood flow
• Skin pH
• Condition of skin
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23. Formula for iontophoresis:
The basic formula for using iontophoresis is:
I x T x ECE = grams of substance introduced
Where:
I: (Intensity) measured in amperes.
T: (Time) measured in hours.
ECE: (Electro-Chemical Equivalent) represents standardized
figures for ionic transfer with known currents and time
factors.
As the determination of the ECE for many complex
substances is very difficult, fewer milligrams of these complex
substances will penetrate the skin.
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24. Conclusion
Iontophoretic drug delivery has developed a new
application system for dermal and transdermal delivery of
drugs that is electro-phoretically self-regulated device with
electronic indicator.
The iontophoretic delivery of macromolecules will open
the doors to non-invasive transdermal delivery of peptide-based
pharmaceuticals.
Iontophoresis has been explored for many dermatologic
and other medical conditions with reports of considerable
success.
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25. REFERENCES
• Iontophoretic transport kinetics of ketorolac in vitro and in vivo:
Demonstrating local enhanced topical drug delivery to the muscle.
T. Gratieri, E. Pujol-Bello, G. M. Gelfuso, J. G. de Souza, R. F. V. Lopez, Y. N.
Kalia. Eur J Pharm Biopharm, 2014; 86: 219-226
• Artusi, M.; Nicoli, S.; Colombo, P.; Bettini, R.; Sacchi, A.; Sanli,P. J.
Pharm. Sci. 2004, 93 (10), 2431-8.
• Banga, A.K.; Chien, Y.W. J. Control. Release, 1988, 7(1), 1-24.
• Banga, A.K.; Bose, S.; Ghosh, T.K. Int. J. Pharm. 1999, 179(1), 1-19.
• Bertolucci, L.E. “Introduction of Anti-inflammatory Drugs by
Iontophoresis: Double Blind Study.” J Orthopedic and Sports Physical
Therapy. 1982;4:103-108 .
• Turning theory into practice: the development of modern transdermal drug
delivery systems and future trends.
O. Perumal, S. N. Murthy, Y. N. Kalia. Skin Pharmacol Physiol, 2013; 26:
331-342
• Controlled iontophoretic transport of huperzine A across skin in vitro and
in vivo: effect of delivery conditions and comparison of pharmacokinetic
models.
D. R. Kalaria, P. Patel, V. Merino, V. B. Patravale, Y. N. Kalia. Mol Pharm,
2013; 10(11): 4322-4329.
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