Evidence-Based Guidelines for Utilization of Dexamethasone

THERAPEUTIC MODALITIES
Tricia Hubbard, PHD, ATC, Report Editor
Evidence-Based Guidelines for Utilization
of Dexamethasone Iontophoresis
Christopher D. Brown, MS, ATC • Rocky Mountain University and Sterling College
and Christine A. Lauber, EdD, ATC • University of Indianapolis
I
ontophoresis involves transmission of
ionized medicated and non-medicated
substances into the skin. 1,2 An electrical
field is produced between two electrodes
that have opposite polarities, which either
repel or attract ions within a medication.3
The basic principle underlying iontophoresis is that opposite charges attract each
other and like charges
repel each other. Thus,
Key Points
medications with a
positive charge will be
Dexamethasone iontophoresis has been
repelled by an elecshown to be effective for inflammatory
trode with positive
conditions, such as carpal tunnel syndrome,
polarity (anode), and
lateral epicondylitis, Achilles tendon
those with a negative
pathology, and plantar fasciitis.
charge will be repelled
There are a wide variety of treatment proby an electrode with
tocols using dexamethasone iontophoresis.
negative polarity (cathode). Lachaud4 studied
Effective treatment depth has been found
the use of corticosteto be < 30 mm below the skin’s surface.
roids in iontophoresis,
which led to the use
of dexamethasone as the primary antiinflammatory medication administered
through iontophoresis treatments. Common
medications used to treat orthopedic conditions through iontophoresis include dexamethasone, acetate, hydrocortisone, and
lidocaine.1,2
Dexamethasone is a common iontophoresis medication used by athletic trainers
because of its anti-inflammatory properties1
and the availability of a noninvasive mechanism to deliver a localized concentration of
the medication.5 The purposes of this report
are to review the current research evidence
pertaining to dexamethasone iontophoresis
and to provide practice guidelines for its use
in athletic training.
Using Dexamethasone to Treat
Inflammatory Conditions
Researchers have assessed the effectiveness
of dexamethasone iontophoresis for treatment of inflammatory conditions such as
carpal tunnel syndrome,6-8 lateral epicondylitis,9,10 Achilles tendon pathology,11 and plantar faciitis.12-14 Table 1 provides a summary of
the available evidence. Two studies involving
patients with carpal tunnel syndrome have
provided evidence that dexamethasone iontophoresis is effective in decreasing symptom
severity and improving functional status.6,
7 The authors of both reports concluded,
however, that injection of the medication was
a better method of administration because
of its higher rate of success. Another study
compared dexamethasone iontophoresis to
a placebo treatment in terms of reduction of
carpal tunnel symptoms and nerve conduction.8 The outcome measures were the Levine
Self-Assessment Questionnaire, SemmesWeinstein Monofilaments, and nerve conduction studies. No significant ­difference
© 2011 Human Kinetics - ATT 16(4), pp. 33-36
international journal of Athletic Therapy & training
july 2011  33
between the treatment group and the placebo group
was reported for any of the outcome measures, suggesting that dexamethasone treatment was no better
than placebo.
Runeson and Haker9 found no statistical difference
in pain-relief between the treatment and control groups
that consisted of 65 patients suffering from lateral
epicondylitis. In contrast, Nirschi et al.10 found that
dexamethasone iontophoresis significantly reduced
short-term pain and inflammation in 99 patients suffering from acute epicondylitis when compared to a
control group of 100 patients.
Neeter et al.11 found that management of Achilles
tendon pain with dexamethasone iontophoresis was
effective in reducing pain at six months compared to
a control group. Gudeman et al.14 found that patients
with plantar fasciitis who were treated with dexamethasone iontophoresis had decreased pain and increased
foot function after one week of treatment compared
to a placebo group; however, those who received the
dexamethasone iontophoresis treatment did not demonstrate a significant difference in pain and function
compared to the placebo group after one month, which
suggests that the treatment had only short-term effectiveness. Osborne and Allison12 found that acetic acid
iontophoresis was more effective in controlling plantar
fasciitis pain than both dexamethasone iontophoresis
and placebo treatments. Contrary to the above studies,
Cleland et al.13 compared dexamethasone iontophoresis to manual therapy (tissue mobilization and joint
mobilization of the ankle, knee, and hip) for treatment
of plantar heel pain. Although dexamethasone iontophoresis was effective in increasing ankle function, it
was not as effective as manual therapy, and it did not
produce change in status that exceeded the Minimal
Clinically Important Difference (MDIC) for meaningful
improvement.
Evidence-Based Treatment Parameters
The practice of athletic training is becoming increasingly reliant on evidence-based guidelines.15 Table 2
summarizes evidence-based treatment parameters for
use of dexamethasone iontophoresis to treat inflammatory conditions.
Iontophoresis treatment dosage is typically measured in milliamp-minutes (mA-minutes), which is
derived from multiplication of the minutes of treatment
by the current intensity (amplitude). For example, if a
patient was treated for 20 minutes at 4 mA amplitude,
then the total treatment dosage would be 80 mAminutes. Treatment dosages for use of dexamethasone
to treat inflammatory conditions are equal to, or less
than, 80 mA-minutes.3,7-10,12-14 Setting the treatment
dosage above 80 mA-minutes can cause skin burns.16,17
Dexamethasone concentration of 0.4% has been used
by a number of researchers.6-10,12,14
Many iontophoresis units have preset limits on the
amplitude or current that can be selected for treatment,
and the current flow will automatically stop when the
Table 1. Summary of the Evidence Regarding Dexamethasone Iontophoresis and Inflammatory Conditions
Pathology
Dosage
Concentration
Current
Treatment Cycle
Benefit Study
Carpal Tunnel
*****
0.4%
*****
6 tx over 2 weeks
Yes
Gökoğlu et al., 20056
10-40 mA-min
0.4%
1-4 mA
5 tx over 3 weeks
Yes
Karatay et al., 20097
80 mA-min
0.4%
2 mA
6 tx over 2 weeks
No
Amirjani et al., 20098
Lateral Epicondylitis 40 mA-min
0.4%
4 mA
4 tx over 2 weeks
No
Runeson et al., 20029
40 mA-min
0.4%
4 mA
6 tx over 2 weeks
Yes
Nirschl et al., 200310
Achilles Tendon
*****
*****
*****
4 tx over 2 weeks
Yes
Neeter et al., 200311
Plantar Faciitis
40 mA-min
0.4%
1-4 mA
6 tx over 2 weeks
Yes
Osborne et al., 200612
40 mA-min
*****
*****
No
Cleland et al., 200913
40 mA-min
0.4%
1-4 mA
4 tx over 2 weeks &
2 tx over 2weeks
6 tx over 2 weeks
Yes
Gudeman et al., 199714
***** Not stated in study
34  july 2011
international journal of Athletic Therapy & training
Table 2. Evidence-Based
Guidelines for Administration
of Dexamethasone
Iontophoresis Treatments
Drug Concentration: 0.4% dexamethasone solution
Amplitude:
1 mA – 4 mA (based on patient’s
tolerance)
Dosage:
80 mA-minutes or fewer (most
studies say 40 mA-minutes)
Treatment Time:
20 minutes or patient’s tolerance based upon amplitude and
dosage
Skin Depth:
< 30mm below the skin
Treatment Cycle:
4-6 treatments over 2-3 weeks
selected treatment dosage has been achieved. The
maximum recommended treatment amplitude in
the literature is 4mA,3,7,9,10,14 but some patients have
experienced discomfort with a treatment amplitude
that is close to 4 mA.7,8,10,14
Treatment cycle refers to the volume of treatment
administered over a period of days or weeks. For the
treatment of carpal tunnel syndrome, Karatay7 administered five treatment sessions per week for three
weeks. For treatment of plantar heel pain, Cleland13
administered two treatments per week for two weeks,
which was followed by one treatment per week for two
more weeks. Both Runeson,9 who was treating Achilles tendon pain, and Neeter,11 who was treating lateral
epicondyle pain, identified four treatment sessions
within two weeks, with three to four days between
treatment sessions, as an effective treatment cycle.
Five studies, two involving carpal tunnel syndrome,6,
8 two involving plantar fasciitis,10,12 and one involving
acute epicondylitis,14 used a treatment cycle consisting of six treatment sessions over a two-week period.
On the basis of studies that have produced positive
outcomes,6,7,10-12,14 a recommended treatment cycle
consists of four to six treatment sessions over a period
of two to three weeks.
Depth of Penetration
A central question about the effectiveness of iontophoresis is the depth of medication delivery. Several
studies have demonstrated that iontophoresis delivers
dexamethasone into the skin to a depth of 30mm.5,1820 Glasset al.6 reported that 30% of a dexamethasone
international journal of Athletic Therapy & training
dose penetrated the skin to a depth of 6-20 mm after
100 mA-minutes (5 mA over 20 mins) of current delivery in Rhesus monkeys.5 The results of this study are
difficult to generalize to a human population, because
most of the current literature relates to research that
has involved human subjects and doses up to 80 mAminutes.3,8-10,12-14 Gurney and Wascher19 and Gurney et
al.20 found that a measurable amount of dexamethasone had been transmitted through the skin and into
human connective tissues at a treatment dose of 40
mA-minutes. Anderson et al.18 tested dexamethasone
iontophoresis on five human subjects with a dosage of
40 mA-minutes and reported a penetration depth of
8-10mm. The results of this study also suggested that
prolonged treatment time increased the concentration
of dexamethasone in the tissues, because passive diffusion was the main mechanism for movement of the
medication through the skin. The collective findings
of the cited studies suggest that dexamethasone can
be delivered to tissues that are less than 30 mm from
the skin surface.
Conclusions
Research evidence supports the use dexamethasone
iontophoresis for treatment of Achilles tendon pathology11 and plantar faciitis.12-14 There is conflicting evidence regarding the effectiveness of dexamethasone
iontophoresis to treat carpal tunnel syndrome6-8 and
lateral epicondylitis.9,10 Only one study, however, has
examined the effects of dexamethasone iontophoresis
in athletic patients.3 Although two studies have used
patients under the age of 40,3,11 the majority of the
available research has involved patient populations
beyond the age of 40.6,8-10,12-14,18 Generalizability of the
study results to the athletic population may limited by
changes in skin permeability associated with aging.21
Additional research needs to be performed to assess
the effectiveness of dexamethasone iontophoresis for
the treatment of athletic injuries. 
References
1.Belanger A-Y. Therapeutic Electrical Agents. 2nd ed. Philidelphia, PA:
Lippincott Williams and Wilkins; 2010.
2.Knight KL, Draper DO. Therapeutic Modalities: The Art and Science.
Philidelphia, PA: Lippincott Williams and Wilkins; 2008.
3.Hasson SM, Wible CL, Reich M, Barnes WS, Williams JH. Dexamethasone iontophoresis: effect on delayed muscle soreness and muscle
function. Can J Spt Sci. 1992;17:8-13.
4.Lachaud JP. Considerations on the use of corticoids by ionization in
certain ocular diseases. Bull Soc Ophtalmol Fr. 1965;65:84-89.
july 2011  35
5.Glass JM, Stephen RL, Jacobson SC. The quantity and distribution of
radiolabeled dexamethasone delivered to tissue by iontophoresis. Int
J Dermatol. 1980;19:519-525.
6.Gökoğlu F, Fndkoğlu G, Yorgancoğlu ZR, Okumus‚ M, Ceceli E, Kocaoğlu
S. Evaluation of iontophoresis and local corticosteriod injection in
the treatment of carpal tunnel syndrome. Am J Phys Med Rehabil.
2005;84:92-96.
7.Karatay S, Aygul R, Melikoglu MA et al. The comparison of phonophoresis, iontophoresis and local steroid injection in carpal tunnel
syndrome treatment. Joint Bone Spine. 2009;76:719-721.
8.Amirjani N, Ashworth NL, Watt J, Gordon T, Chan KM. Corticosteriod
inotophoresis to treat carpal tunnel syndrome: a double-blind randomized controlled trial. Muscle Nerve. 2009;39:627-633.
9.Runeson L, Haker E. Iontophoresis with cortisone in the treatment
of lateral epicondylagia (tennis elbow)-a double-blind study. Scand J
Med Sci Sports. 2002;12:136-142.
10.Nirschl RP, Rodin DM, Ochiai DH, Maartmann-Moe C. Iontophoretic
administration of dexamethasone sodium phosphate for acute epicondylitis. A randomized, double-blinded, placebo-controlled study.
Am J Sports Med. 2003;31:189-195.
11.Neeter C, Thomee R, Silbernagel KG,P Thomee Karlsson J. Iontophoresis with or without dexamethazone in the treatment of acute Achilles
tendon pain. Scand J Med Sci Sports. 2003;13:376-382.
12.Osborne HR, Allison GT. Treatment of plantar fasciitis by low dye
taping and iontophoresis: short term results of a double blinded,
randomised, placebo controlled clinical trail of dexamethasone and
acetic acid. Br J Sports Med. 2006;40:545-549.
13.Cleland JA, Abbott JH, Kidd MO et al. Manual physical therapy and
exercise versus electrophysical agents and exercise in the management of plantar heel pain: a multicenter randomized clinical trial. J
Orthop Sports Phy Ther. 2009;39:573-585.
14.Gudeman SD, Eisle SA, Heidt RS, Colosimo AJ, Stroupe AL. Treatment
of platar fasciitis by iontonphoresis of 0.4% dexamethasone. Am J
Sports Med. 1997;25:312-316.
15.Manspeaker SA, Van Lunen B. Implementation of evidence-based
practice concepts in undergraduate athletic training education: experiences of select educators. Athl Train Educ J. 2010;5:51-60.
16.Guffy JS, Rutherford MJ, Payne W, Phillips C. Skin pH changes associated with iontophoresis. J Orthop Sports Phy Ther. 1999;29:656-660.
17.Leduc BE, Caya J, Tremblay S, Bureau NJ, Dumont M. Treatment of
calcifying tendinitis of the shoulder by acetic acid iontophoresis: a
double-blind randomized controlled trial. Arch Phys Med Rehabil.
2003;84:1523-1527.
18.Anderson CR, Morris RL, Boeh SD, Panus PC, Sembrowich WL. Effects
of Iontophoresis current magnitude and duration on dexamethasone
deposition and localized drug retention. Phys Ther. 2003;83:161-170.
19.Gurney AB, Wascher DC. Absorption of dexamethasone sodium phosphate in human connective tissue using iontophoresis. Am J Sports
Med. 2008;36:753-759.
20.Gurney B, Wascher D, Eaton L, Benesh E, Lucak J. The effect of skin
thickness and time in the absorption of dexamethasone in human
tendons using iontophoresis. J Orthop Sports Phys Ther. 2008;38:238245.
21.Farage MA, Miller KW, Elsner P, Maibach HI. Functional and physiological
characteristics of the aging skin. Aging Clin Exp Res. 2008;20:195-200.
Christopher D. Brown is an assistant professor and Head Athletic
Trainer at Sterling College in Sterling, KA. He is also a doctoral student
at Rocky Mountain University of Health Professions.
Christine A. Lauber is an associate professor and Clinical Education
Coordinator at University of Indianapolis.
Human Kinetics is pleased to bring you convenient, free
online learning opportunities through our monthly Raising the
Bar webinars. This webinar series will provide athletic trainers,
personal trainers, and strength and conditioning coaches
with an excellent way to learn information and further their
education. Raising the Bar addresses a variety of topics and
resources relating to fitness, nutrition, and health. From the
comfort of your home or office, you have access to these live
web-based presentations conducted by leading authorities in
their respective areas of expertise.
Reserve your webinar seat now!
Visit www.HumanKinetics.com/RaisingTheBar to register
or view recorded events.
Share.
Learn.
Grow.
1219
36  july 2011
Human Kinetics also offers several other webinar events
addressing a variety of topics and resources relating to sports,
coaching, nutrition, training, physical education, recreation,
and more. Visit our website for details.
Human Kinetics
The Information Leader in Physical Activity & Health
2/11
international journal of Athletic Therapy & training