Iontophoresis Flashcards
What is Iontophoresis?
The application of a continuous direct current to transport medicinal agents through the skin or mucous membrane for therapeutic purposes.
What conditions is iontophoresis used for?
tendinitis, bursitis, tenosynovitis, arthritis, plantar fascitis, patellar tendinitisl, achilles tendinitis
What law does iontophoresis use for tx?
Coulomb’s Law: like charges repel like charges; unlike charges attract unlike charges
What is the wave form, modulation, & current type of iontophoresis?
monophasic wave form, continuous modulation, & low intensity direct current (LIDC)
What is the current range that iontophoresis can be set at?
0.5mA and 4mA
What are the 2 polar effects?
- positive ions move toward the negative pole (cathode) where a secondary alkaline reaction (NaOH) occurs 2. Negative ions move toward the positive pole (anode) where an acid is produced (HCl)
When delivering medication from the ____ it usually produces more skin irritation. This is due to NaOH (aka Lye), a caustic soda metallic base to form. The NaOH causes a caustic reaction on the skin.
cathode
The number of ions transferred is directly related to what 3 things?
treatment time (duration), current density, concentration of the ions in the solution
What determines the rate at which an ion may be delivered?
concentration of the ion, pH of the solution, molecular size of the solute, current density, duration of the treatment
What are the advantages of taking medications via transdermal iontophoresis relative to oral medications?
concentrated in a specific area, does not have to be absorbed within the GI tract, safer than administering a drug through injection
What does iontophoresis and phonophoresis have in common?
both techniques deliver chemicals to biologic tissues
What are the differences between phonophoresis and iontophoresis?
Phonophoresis uses ACOUSTIC ENERGY (ultrasound) to drive MOLECULES into tissues. Iontophoresis uses ELECTRICAL CURRENT to transport IONS into tissues.
What is an acidic reaction of iontophoresis?
an acidic reaction from ionto is sclerotic in nature and causes hardening of the skin
What is an alkaline reaction of iontophoresis?
an alkaline reaction is sclerolytic and softens the skin exposing it to irritation and burns during further treatment
What is buffering as it relates to iontophoresis?
buffering is a technique used to stabilize the pH of the skin during iontophoresis, by placing buffering agents into the electrode pad that has the drug. It maintains H+ concentration and avoids pH change during treatment.
What is the procedure for using iontophoresis?
clean and inspect skin, position patient and support treatment area, do not lie on the electrodes, unit on continuous direct current, massage solution into treatment site (or on electrode depending on unit type). Place the approproate-sized active electrode (whether + or -) on treatement area.
The active electrode should be the ___ polarity as the medicinal ion
same
To reduce the alkaline effect on the skin, the ___ electrode should be ___ as large as the positive regardless of which is the active electrode or medication type.
negative, twice
How far away is the dispersive electrode placed and where?
4-6 inches away proximal or distal; commercial electrode sets have a fixed distance that limits the spacing between electrodes.
What is the dosage of the anode?
1 mA/cm2
What is the dosage of a cathode?
0.5 mA/cm2
What is the duration range of iontophoresis tx?
10-40 min
What is the max amplitude for iontophoresis? What is the rule of thumb?
max of 5mA, rule of thumb 4mA
How often do you check the treatment area for iontophoresis?
3-5min
After treatment, remove electrodes, clean the area & ____.
apply lotion to pt.
When using iontophoresis to treat pain & inflammation, the current-dosages range from ___ to __
40mA x min (usual), 80mA x min (max)
The glucocorticoid Dexamethasone is used for their _____ effects. This is a (+/-) charge. Prolonged use of glucocorticoids when used for a prolonged period of time can have a catabolic effect on collagen.
anti-inflammatory, negative charge
Which 3 medications have been used for their analgesic effects?
local anesthetics, salicylates, & opiods
____ has been used to treat soft tissue calcification. It is delivered from the cathode.
acetic acid
The 5 negatively charged therapeutic ions are:
Acetate, Dexamethasone, Iodine, Salicylate, Chlorine [remember A—D-I-S-C]
What are the 6 positively charged therapeutic ions?
Hydrocortisone, Histamine, Lidocane, Lithium, Magnesium, Zinc
Which 3 ions are used for analgesia?
Lidocane, Xylocaine, Salicylate
What ion is used for calcium deposits?
Acetate
Which ion is used for dermal ulcers?
zinc
Which ion is used for edema?
Hyaluronidase
Which ion is used for fungal infections?
copper
Which ion is used for hyperhydrosis?
water
Which 2 ions are used for muscle spasms?
calcium & magnesium
Which 2 ions are used for musculoskeletal inflammatory conditions?
Dexamethasone & Hydrocortisone
What are the 3 precautons for iontophoresis?
DO NOT USE for broken skin, areas of decreased circulation, & over or near implanted electrical devices
What are the contraindications for iontophoresis?
refer to general rules for e-stim, impaired skin sensation, allergy or sensitivity to therapeutic agent or direct current, denuded area or recent scars, cuts, bruises, or broken skin, metal in or near tx area
Which condition can be diagnosed & monitored with iontophoresis? How is this done; include the drug used?
Cystic Fibrosis; diagnosed and minitored using the sweat-test involving the application of a medication that stimulates sweating (pilocarpine) to one electrode of an apparatus and running electric current to a separate electrode on the skin. The sweating is colleced on filter paper or in a capillary tube and analyzed for abnormal amounts of sodium and chloride. People with CF have increased amounts of sodium and chloride in their sweat glands.
What symptoms would prompt a sweat-test?
poor growth, many respiratory infections, or foul-smelling stools. In some states, newborn screening programs test for cystic fibrosis, and the sweat test is used to confirm these results.
