Iontophoresis?

What Is Iontophoresis?

Iontophoresis is a technique using a small electric charge to deliver a medicine or other chemical through the skin. Basically an injection without the needle. The technical description of this process is a non-invasive method of propelling high concentrations of a charged substance, normally medication or bioactive agents, transdermally by repulsive electromotive force using a small electrical charge applied to an iontophoretic chamber containing a similarly charged active agent and its vehicle. To clarify, one or two chambers are filled with a solution containing an active ingredient and its solvent, termed the vehicle. The positively charged chamber, termed the anode will repel a positively charged chemical, while the negatively charged chamber, termed the cathode, will repel a negatively charged chemical into the skin.

Lectroject drug delivery system

Iontophoresis

There has been a resurgence of interest in iontophoresis in the medical profession. Why call it a renaissance of iontophoresis in this day and age? We've known about galvanic current for about 200 hundred years and iontophoresis (a word derived from Greek meaning the transport of electrically charged chemicals called ions) through skin was demonstrated almost 100 years ago.

Skin care therapists have used galvanic currents to treat skin for about 70 years -so what can be new? First activate the skin on negative current, then massage and finally soothe the skin on positive for a refreshed appearance. Right? No! Wrong!

Of course these ideas are wrong because they ignore the basic scientific principles. First of all one has to understand that iontophoresis will only occur if the targeted active chemicals have an electrical charge (i.e. they are ions carrying either a positive or negative electrical charge, or will ionise with electricity). When a low intensity galvanic current is applied to a molecule that can dissociate into a positive ion (cation) and a negative ion (anion), then it dissociates more readily in the presence of water and salts. Negative ions move towards the positive pole, and positive ions move towards the negative pole. As a result ions can be carried to deeper layers of the skin and concentrated there.

If a positive current is applied to the skin together with appropriate gels, then the positive pole will act exactly like a magnet (North Pole repels North Pole and alternately South Pole and vice versa) and repel cations and attract anions. Therefore, if one wants to facilitate the penetration of a cation then one has to apply a positive charge to the skin. However, if one wants to make an anion penetrate deeper into the skin, then one has to apply a negative charge.

To understand iontophoresis better, then one must go back to the very first demonstration of its power. Two rabbits were selected and one poison that has a positive charge was applied to one ear and a poison with a negative charge was applied to the other ear. Only one ear was treated with an electrical current. When the positively ionised poison was treated with a negative current, nothing happened. When positive current was used then the rabbit died! So either positive current was responsible, or the positive poison ions moved through the skin into the blood and killed the rabbit. The second rabbit then proved that it was the ions because when a positive current was used, nothing happened, whereas when a negative current was used, the rabbit died! The only explanation was that the positive and negative ions had been repelled by their similar charges and had gone through the skin.

This was a magnificent demonstration but unfortunately not enough people paid attention to it and it was lumped together with things like hypnosis and ignored by the medical profession. In recent years, research workers have looked again at iontophoresis and have tried to define its mysteries. As a result we've learned a great deal about iontophoresis and today research workers believe that iontophoresis can very often be as effective as injections into the skin or muscles. Diabetics may one day wear only a simple instrument like a watch and in that way dose themselves with enough insulin to keep them selves healthy. Other powerful medicines can even be taken more than 2 cms. Into the body by simple electrical currents. Iontophoresis promises to become a major method for treating people without the use of injections and other invasive techniques. The research workers have realised that we have to know certain properties about ions, not merely that they can ionise. When a molecule that can be ionised at an appropriate pH is subjected to a galvanic current, the molecule ionises into its anion and cation. We have learned that the concentration of the ions is important. The strongest solution is not always the best. We also know now that the properties of the current are important. Certain wave shapes and intermittent application of the current are better than continuous galvanic current.

There are some very important rules that have to be followed when doing iontophoresis.

The selected molecule must be ionised into positive and negative components and be maintained as ions during the treatment. You cannot iontophorese chemicals that are not ionised.
The size of the ion is important. For example even though a complex protein like collagen may be possible to ionise, the size of the important ion of collagen is so large that it cannot be transported through skin.
There is a limit to the number of polar substances that can be used simultaneously. We believe that during iontophoresis "pores" open up through membranes and the charged particles can move through them. If there are too many charged particles then the "pores" may be "blocked" by the crowd of ions converging all at once.
The ion must be water-soluble because electricity is only conducted through water and not lipids.
The pH of the active gel is of fundamental importance. The right ingredient at the right concentration won't work properly if the pH is wrong. Each ion has it's own ideal pH at which it will be ionised best.
The current used must be appropriate. You cannot use any current you like.
The current used should be high enough to be effective and still safe. The higher the current, the faster the ions will move.
Intermittent current works better than continuous current because as the ion moves into the skin it will react with other chemicals and needs to be re-ionised.
The treatment period should be at least 10 minutes and probably not longer than 30 minutes. Most of the ions pass through the skin at about 8 to 15 minutes and then relatively little passes through after 30 minutes.
It is possible, maybe even highly desirable to treat skin with only one polarity. It is not necessary to treat the skin with the opposite current after doing the active treatment. If you do that then you will reverse the beneficial effects of the active treatment!
Of course, the ion will only have positive effects if in fact scientific research has proved that it is effective. We recently discovered that Acyclovir administered through the Lectroject iontophoresis system is capable of flushing out (waking up) the herpes virus from hiding. Which is actually a good thing because now the medication can kill off the virus. The theory is that by activating the herpes virus, then preventing it from returning to hibernation, it can be completely eradicated with this treatment.

Iontophoresis when correctly used is proving to a be a powerful tool. With properly controlled iontophoresis up to 400% better penetration can be achieved under ideal conditions. Modern Lectroject iontophoresis has been used to completely eliminate herpes, cytomegalo and the coxsackie B group of virusses.

Close Window