FAQs: Hyperhidrosis & Iontophoresis Treatment

Answers to common questions about iontophoresis and hyperhidrosis

We have summarized the answers to the most frequently asked questions about iontophoresis and hyperhidrosis here.

For more complex or individual questions about your therapy, you can contact our iontophoresis experts via WhatsAPP at +492056981110 or by calling +49 (0) 2056/98 11 0.

Health questions about hyperhidrosis and iontophoresis treatment

What is hyperhidrosis?

The term hyperhidrosis refers to excessive sweating that goes beyond the body’s need for thermal regulation. People with hyperhidrosis sweat excessively, regardless of physical exertion or ambient temperature. This dysfunction can lead to significant mental, social, and occupational limitations and can thus cause a marked reduction in the quality of life.

Hyperhidrosis can occur in different parts of the body. Hyperhidrosis often occurs on the hands (hyperhidrosis palmaris), on the face (hyperhidrosis facialis), on the soles of the feet (hyperhidrosis plantaris), and in the armpits (hyperhidrosis axillaris). There are two types of hyperhidrosis Primary or focal hyperhidrosis occurs independently of other diseases. Secondary hyperhidrosis occurs as a result of an existing, underlying condition or as a side effect of taking medication or dietary supplements.

When should I NOT do tap water iontophoresis?

Treatment with iontophoresis devices must never be used in patients:

  • with pacemakers
  • with defibrillator implants
  • who are pregnant
  • who have an IUD containing metal (no treatment of the feet)
  • with metal implants near the region where the current is to be applied
  • with major skin defects/wounds that cannot be covered with Vaseline
  • with areas of skin near the treatment area with limited or no sensitivity (e.g. polyneuropathy)
  • with major wounds, rashes, swelling, localized inflammations, or acute local infections
  • diagnosed or suspected heart issues or epilepsy

Do NOT apply the electric current directly to the chest, the brain, or the sinus cavities!

I have an IUD. Can I have an TWI treatment?

If your IUD is not completely encased in plastic, then you should NOT let your feet be treated. If the IUD is completely encased in plastic, silicone, or similar material, then the metal is insulated and treatment may be performed.

I am pregnant. Can I have an TWI treatment?

Do NOT get treated with TWI if you are pregnant. No studies or empirical data on TWI treatment with HIDREX devices during pregnancy are available. We therefore strongly advise against being treated while pregnant.

I am nursing my baby. Can I have an TWI treatment?

Yes. However, the baby should not be on the chest or have skin contact with the mother during the treatment.

I have metal implants. Can I have an TWI treatment?

Basically, all metal implants are an absolute contraindication. If the implants are in the direct range of the current flow, no treatment should be performed. If the implant is not in the direct range of the current flow, it is a relative contraindication. The risk of its causing problems is rather low, but please consult with your physician before accepting treatment.

I have pain in some parts of my skin during treatment. Can I do something about it?

Small skin defects, such as scratches or cracks should be covered thickly with Vaseline. The water level should avoid the nail bed as frequent micro injuries here can lead to pain during treatment.

What are the typical signs of primary, focal hyperhidrosis?

  • onset of symptoms in childhood, adolescence, or early adulthood (usually by age 25; with hand symptoms usually occurring before puberty)
  • sweating regardless of temperature, unpredictable, and not willingly controllable
  • localized occurrence in one or more sites prone to a disease with bilateral, symmetric involvement
  • occurs more than once a week and impairs the quality of everyday life
  • no increased sweating during sleep
  • positive family history

How does my doctor diagnose hyperhidrosis?

The diagnosis of primary, focal hyperhidrosis is made mainly by interviewing the patient and physical evidence of sweat production. In addition, the iodine-starch test and a quantitative measurement of sweat levels can be performed.

I have to wear a long-term ECG. Can I have an TWI treatment?

A long-term ECG examination is not an absolute contraindication for TWI. Nevertheless, we do not recommend concomitant treatment. During the usually 24-hour ECG recording, the TWI therapy can be paused without negative impact on your therapy.

My skin is very dry following the treatment. But why is this the case?

During the treatment a reversible changing of the acid-base balance of the skin occurs by means of ion transport. This results in the positive and desired effect of the skin being dry and reducing excess sweating.

Our top tip: Apply cream to your skin following treatment (never before therapy!) The skin should be degreased prior to treatment. Prior to treatment thoroughly wash the area to be treated in order to remove any residual cream.

Technical questions about Hidrex iontophoresis devices

Are HIDREX devices safe and tested?

We are authorized to manufacture medical devices in accordance with EU Directive 93/42/EEC and are therefore authorized to issue the medical CE mark for our medical devices.

In addition, our TWI devices have been registered by the US Food and Drug Administration. For your safety we maintain a supervised quality management system for medical devices and are certified according to EN ISO 13485:2016.

What are the components of an iontophoresis device?

Each iontophoresis device consists of 4 device components:

  • Controller (e.g. HIDREX connectION)
  • Special accessories for the areas of the body to be treated (e.g. ergonomic treatment basins for hands and feet, axillary applicators, face masks)
  • Treatment electrodes (to transfer the electricity to the water)
  • Connection double cable (for the transmission of the current from the control unit to the treatment electrodes)

Why is the operation of the device with a plug-in power adapter harmless, although other devices are operated with batteries or rechargeable batteries?

Technically, you have to imagine that the treatment circuit is completely disconnected from the power supply and thus (even in case of a serious fault) has NO connection.

This is called a “galvanic separation”.

This absolutely important technical security is already ensured directly in the power adapter, so that the mains voltage cannot reach the device at all.

For this reason, only the supplied original medical power adapter may be used.

My power adapter is defective. Can I buy a replacement one at the hardware store or electronics store?

No, it is essential to use only the original power adapter with medical approval. The power adapter is a decisive factor for the overall safety of the therapy device and has to be approved for medical devices in addition to the special technical requirements.

Such power adaptors are usually not available in retail stores. Only when using the original power adapter can the safety be ensured (see above).

Consider the power adapter as part of the therapy device and not just as another accessory.

My therapy device is not working. Why would that be?

In about 90% of cases, the cause is a wrong setup. Please note that both treatment electrodes cannot be in the same basin.

Turn on the device first, then place your hands or feet in the treatment tubs. Clamp the AX set to the armpits only after switching it on.

For further troubleshooting, please first use the following checklist before returning the device for repair. You may save yourself and us time, effort, and costs.

  • Verify that the safety power adapter is properly connected to the base unit and to your electrical outlet.
  • Check that the connectors of the connecting double cables have been pushed far enough onto the connections of the treatment electrodes for a secure contact.
  • Check if the device is working properly with another person; it may be that the over therapy protection function has been activated.

Tip:     In rare cases, the tap water used may not have a sufficient conductivity (e.g. when the tap water has been deionised). In these cases, try using bottled water (without carbonation).

Also note the instructions for the care of the iontophoresis device. Lime deposits on the electrodes can hinder the flow of the current.

Please contact us if you have any questions. Thank you!

Why should I choose a HIDREX device?

Our HIDREX devices have been proven to have a 98% success rate. For more than 35 years, we have developed highly effective, first-class therapy systems in collaboration with doctors, university hospitals, and therapists.

We consistently focus on the use of the latest technologies and high-quality components to develop and manufacture certified medical devices for innovative, natural healing processes. Using both DC and pulse current makes our devices highly flexible and effective.

Thanks to adjustable pulse range, our devices combine the best advantages of both types of current. High voltages make speedy therapy success possible. Technical features, such as the ASE anti-shock electronics further ensure safety and comfort.

We are authorized to manufacture medical devices in accordance with EU Directive 93/42/EEC and are therefore authorized to issue the medical CE mark for our medical devices. In addition, our TWI devices have been registered by the US Food and Drug Administration.

For your safety we maintain a supervised quality management system for medical devices and are certified according to EN ISO 13485:2016.

The electrodes are showing discoloration. What can I do?

It is normal for the electrodes to discolour slightly after a few applications. The discoloration has no influence on the treatment results.
The texture of water has influence on the discoloration, so that discoloration can vary depending on the water supply in the region.

If you do not suffer from a nickel or chromium allergy, we recommend using the stainless steel electrodes as the risk of discoloration of the electrodes is lower and they are much faster and easier to clean.

Please observe the care instructions for the electrodes.

My device is less effective than it once was. Is it broken?

It is very rare that a device is broken. In almost all cases, contaminated electrodes are the cause; these can lead to reduced therapeutic effectiveness.

Lime deposits on the electrodes can hinder the flow of the current. These deposits can be removed with household lime removers, vinegar, or citric acid.

Please observe the instructions for care of the electrodes.

How do I properly care for my electrodes?

After each treatment, rinse your metal electrodes with clean water and carefully wipe the plates with a soft cloth to prevent limescale. Every 5 treatments or so, you should clean the electrodes with a damp cloth and commercial detergent or a surface disinfectant.

What can I do if my electrodes have deposits?

Over time, calcium and mineral deposits can accumulate on the electrodes. Therefore, every 3 to 6 months (depending on the hardness of your tap water), you should place the electrodes overnight in a 50:50 solution of water and vinegar. The next day just wipe with a towel and then rinse off. You can also use commercial decalcifiers.

My device is not reaching the voltage level I set. Is it broken?

It is very rare that a device is broken. Occasionally, we receive feedback from new customers that the voltage is not getting as high as you have set it or that the voltage drops slightly after setting.

In this case, it is very likely that the current limit function has been activated. This happens when a person’s electrical resistance is very low due to heavy sweating. Due to the easier flow of current, the maximum treatment current can be reached before the set voltage is reached. A protection circuit (current limit) intervenes in this case and prevents the voltage from rising too high to protect you from burns. The therapeutic effect is not affected by this!

Over time, you can slowly increase the voltage values as your sweating levels decline (the electrical resistance of the drying skin increases, so that higher current values are necessary for the device to be effective).

How can I check the function of my HIDREX device?

To check the function of your HIDREX classicION or connectION, follow these steps:

  1. Set up the device as if you wanted to start the treatment.
  2. Switch on the control unit at the main switch. The display should show treatment dose and duration.
  3. Now close the therapy circuit by placing one electrode on the towel of the second electrode without touching the electrodes directly. Now place both electrodes on top of each other and separated by a towel in a basin filled with water. When using the AX electrodes, press the two sponge pads soaked in water directly against each other.
  4. The device should now display the dose indication constantly and the voltage should rise to set value starting from 4V.

If he treatment does not start with this setup, even taking the error checklist into account, please contact us in order to coordinate the further procedure.

Do I have to download the MyHIDREXApp in order to operate the HIDREX connectION and HIDREX conceptION device models?

No! All device models can also be operated without the app. The therapy time, however, is fixed and can only be used with the HIDREX connectION device via the app. You cannot access other additional functions such as, for example, creating therapy protocols without the app.

What is anti schock electronics (ASE)?

All HIDREX devices have a special integrated feature called anti-shock electronics (ASE). This function almost completely prevents the occurrence of light electric shocks (pasture fence effect). For example, when interrupting the circuit, such as when removing hands or feet from the treatment tubs during the current therapy.

The ASE ensures more safety during your therapy and makes handling easier. Even if the so-called pasture fence effect is harmless, it can nevertheless be unpleasant.

It is important to note that ASE is only activated when the device is switched on. It is therefore highly recommended always to separate the area to be treated from the water source (remove hands or feet from the water or remove the pads and electrodes from the armpit or face) before turning off the device.


Questions about the purchase/rental of Hidrex iontophoresis devices for hyperhidrosis treatment

Will my health insurance cover the costs for TWI therapy?

The statutory and private health insurance companies in Germany usually cover the costs of a home iontophoresis device for hyperhidrosis therapy.

Depending on the policy, this provision may cover a one-off purchase or a device rental (only for Germany). Before the insurers promises to pay, your treating physician will often have to provide evidence that the iontophoresis treatment is effective.

For this purpose, an initial treatment round of about ten sessions will have to be performed before you can have your own device prescribed. This initial therapy is carried out at the doctor’s practice or with a loaner device at home (see below).

If the insurance company approves a device rental, as is the case with such companies as Techniker Krankenkasse, a follow-up prescription will be required after the three-month trial phase and then again every two years.

I was recommended to rent an iontophoresis device from you. How does that work?

First of all, it is important to know what your insurer will cover.

If you are covered by statutory health insurance in Germany, then download the rental agreement from our homepage (only for Germany) and send it back to us filled in and signed . We will provide you with a loaner device for free for 5 weeks. Shortly before the expiry of the 5 weeks, we will need a corresponding medical prescription from your doctor or you will send the device well packed and with sufficiently postage back to us.

Are you insured with Techniker Krankenkasse? Then we need a medical prescription right from the beginning.

If you are covered by private health insurance in Germany, then download the rental agreement from our homepage (only for Germany) and send it back to us filled in and signed . We will provide you with a loaner for free for 5 weeks. In addition, you will receive an offer to purchase from us which you can submit to your health insurance. Shortly before the expiry of the 5 weeks, you can send the corresponding purchase order approved by your insurance or you will send the device well packed and with sufficiently postage back to us.

Does HIDREX offer me free help and support for any questions or concerns?

Yes! If you have questions or concerns with your TWI therapy, please contact us.

You can reach our customer service quickly via WhatsApp at +49 (0) 2056 / 9811-10. You can also email us at . You can reach us by phone at +49 (0) 2056 / 9811-0.

Will I have to buy replacement parts on a regular basis?

For the treatment of the hands or feet, your treatment set will contain cotton towels to cover the electrodes. Over time, the towels will wear with time.

You can replace them with HIDREX towels which are cut and sewn to fit in our transport and treatment case and in our ergonomic treatment basins.

You can also use your own towel.

We recommend a white cotton towel (no dyes) to cover the electrodes and to prevent your skin from directly touching the electrodes during treatment.

For the treatment of the armpits or other body parts, you will need special sponge pads which have to be replaced every 1-2 years.

Can I borrow a TWI device from HIDREX?

Yes. To test a device or to perform the initial phase at home, you can borrow an iontophoresis device for free for 5 weeks (only for Germany).

Download, complete, and sign our rental agreement (only for Germany), then return it to us.

Where can I buy a HIDREX device?

HIDREX iontophoresis devices can be ordered from anywhere in the world. You can contact us directly or also one of our long-standing sales partners. Click here for an overview of our global distributors.

Questions about treatment with tap water iontophoresis

What is tap water iontophoresis (TWI) and how does it work?

TWI therapy uses tap water and a low-voltage electrical current to treat excessive sweating on the feet, hands, etc.

Compared to other available treatments, tap water iontophoresis (TWI) is considered to be the most effective, safest, and most affordable treatment for excessive sweating of the hands, feet, armpits, or face.

TWI is a treatment method that has been scientifically recognized for many years and can result in normally dry skin in 98% of cases without medication or surgery. Research, however, has yet to identify exactly why it is so effective. It is believed that the TWI disrupts the way stimuli and secretion are coupled in the sweat glands.

It causes a postsynaptic, but reversible functional disorder, with the result that less or almost no sweat can escape from the sweat glands.

What is the treatment procedure?

Treatment with TWI is similar to working out: the quality of the results depends on how disciplined you are at doing your exercises.

The treatment is carried out by hand and foot baths or by treatment of the armpits, face, neck, or back with special sponge applicators through which weak DC or variable pulse electrical currents are passed.

The therapy starts with the initial phase, a daily 15-minute treatment for 10 days, in which the sweating is reduced to normal levels. Afterwards, 1-2 treatments a week are usually sufficient to maintain the results.

The therapeutic effect is reversible, so if treatments stop, the sweating will resume after some time.

How often should I perform the treatment?

In the initial phase, treatment should be done daily or every other day.

Improvement should be seen after about 10 to 20 treatments. There are significant individual differences in the subsequent maintenance phase.

Some patients need to be treated 3 times a week, others only 2 times a month. Patients will need to determine this through trial and error.

Do I have to do the therapy regularly?

Yes! The tap water iontophoresis causes a reversible disruption to the function of the sweat glands.

The treatment inhibits the sweat glands and allows them to “ignore” the (excessive) nervous signals from the brain which cause excessive sweating.

Without further TWI treatments, the excessive sweating will start again. Regular maintenance treatments are needed to ensure continued successful results.

Is it possible to treat my hands and feet at the same time?

Yes! The Duo Set together with the ergonomic basins makes it possible to treat both your hands and feet in one session.

However, this is not always recommended, but only if you are treating the hands and feet with the same type of current and voltage for the same duration. The Duo Set does not allow different treatment parameters to be set for the hands and feet.

I received an electric shock during treatment. What happened?

That happens every now and then, but very rarely compared to older models or competitive devices! These are always completely harmless, but also sometimes unpleasant voltage spikes (or voltage drops, which feels almost identical).

If, for example, you keep your hands in the water when switching on the device, you might get a slight shock. Short brownouts in the mains supply as well as loose contacts in the power adapter or the electrode connection are further possible causes for this effect.

We recommend slowly taking your hands or feet out of the treatment basins and not jerking them out.

I can feel the current on one side more than on the other. Is my device defective?

No! The electrical circuit used for treatment has electricity running in two different polarities: cathode (black cable, negatively charged) and anode (red cable, positively charged).

Although it has been scientifically proven that the anode is somewhat more effective, there is no consistent customer feedback on this topic.

Some customers feel the positive side more, others the negative ones. This is normal and okay.

What is the difference between direct current (DC) and pulse current (PC)?

Direct current (DC) has the strongest effect because its output is 100% without pauses. However, oversensitivity to the current flow sometimes means using DC at too low a dose or not at all on sensitive skin areas.

DC is still used to treat the feet. With pulse current (PC), the current flow jumps at equally long intervals between ON (50% pulse) and OFF (50% pause).

These intervals reduce the feeling of the current. However, the pauses make PC less effective than DC.

In the treatment of sensitive skin areas, however, the PC is definitely the better choice.

Is DC or pulse current better?

DC is significantly more effective because the patient receives the full amount of electricity at all times. The disadvantage, however, is that you can feel it at all times, too. Pulse current is hardly noticeable at certain voltages, but usually requires longer treatment times to be effective.

Also, higher voltages are easier to endure, better enabling treatments to such sensitive areas as under the armpits or the palms and the treatment of children.

HIDREX’s pulse current combines the comfort & effectiveness and is only available in the PSP 1000.

What is variable pulse current (VPC)?

VPC can be described as a mixture of DC and PC, which combines the best of both types of current. With VPC, it is possible to extend the ON-phases compared to the OFF-phases within a cycle (e.g. 90% pulse, 10% break).

The shorter pause times transmit much more energy than the standard pulse current. This ability to adjust the pulse range increases the effectiveness compared to the conventional pulse current AND the comfort compared to DC current.

VPC is thus the most effective form of current and allows optimal consideration of the individual needs and sensitivities of patients.

For the treatment of children and of sensitive skin areas in adults, VPC is the best choice.

Do I have to change the polarity (polarity) during the treatment?

In principle, the effect of HIDREX therapy does not depend on the polarity of the current.

However, clinical studies have shown that the anode (positive electrode, connection A) is slightly more effective at the beginning of the treatment series than the cathode (negative electrode, Connection B).

Devices without automatic polarity switching

When treating the hands, we recommend not changing the polarity until one side has reached the desired skin dryness. If one side is dry enough (e.g. the right hand) the polarity should be changed once for the further sessions until the second side (e.g. the left hand) has reached the desired effect. Afterwards, the polarity should be swapped for each treatment session, as with the treatment of the feet or armpits in general.

The polarity can be swapped by simply switching the cathode (B) and anode (A).

Devices with automatic polarity switching

To ensure a consistent treatment outcome on both treatment sides from the beginning, you can automatically change the polarity of devices equipped within a single treatment session. This feature can be enabled or disabled as needed. The advantage of this is that you won’t need to remember which polarity you need to use for each session.

Are there any studies on the efficacy of tap water iontophoresis?


The effect of tap water iontophoresis has been scientifically proven for many years. For study results on the efficacy of tap water iontophoresis using HIDREX devices, see here.

Despite initial success, the sweating got worse again. What can I do?

It is possible that your body has become “used to” the flow of electricity and the therapy is currently not working properly. You can try to treat with higher voltage, to extend the pulsed-width or switch to DC. If that does not help, stop your therapy for 2-3 weeks until the sweating returns completely. Then start your therapy again as at the beginning of your TWI treatment.

What is the benefit of the automatic polarity change halfway through the treatment time?

Clinical studies have shown that the anode (positive electrode, connection A) is slightly more effective at the beginning of the treatment series than the cathode (negative electrode, connection B). During the automatic polarity change halfway through the treatment time a simultaneous treatment of both sides occurs from the outset. The advantage of this is that you won’t need to remember which polarity you need to use.

When treating the face why should I not change the polarity?

As the anode (positive electrode, connection A) is, in effect, much stronger than the cathode (negative electrode, connection B) it is more effective for facial therapy if it is only treated with the anode. During treatments, where both sides have to be treated (hands, feet, armpits) the polarity should be switched regularly for an even treatment result.


During treatment with the face mask, should a hand or foot be treated as well? Does this negatively affect the treated hand/foot?

Due to the low dose used to treat the face, no negative effects are to be expected on the hand or foot. In order to further reduce the effect of therapy on the hand or foot, the hand or foot can be altered from therapy session to therapy session.



I have a home filter system (e.g. descaling / carbon reducer). Does this affect the success of my therapy?

Yes, the composition of the water has an effect on tap water iontophoresis. In the context of tap water iontophoresis therapy, care should be taken that no deionised or demineralised water is used, as this has a very low electrical conductivity and the therapeutic effect would be lost.

If you use home filter systems, for example for decalcification, you should not use the tap water for your therapy. Make sure you have a sufficient concentration of calcium, magnesium and salts in the water. Information about your water quality can be obtained from your local water supply company.

Basically this means: Any normal water is good and can be used for tap water iontophoresis. If you have doubts about your water quality, use simple table water. You can also try to add some salt to the water to improve the treatment outcome.

Can aluminium-containing antiperspirants be used in addition to tap water iontophoresis?

No! Please do not use antiperspirants or aluminium-containing deodorants in the same areas that you are treating with iontophoresis as this may cause burns in the treated area. The aluminium particles can diffuse into the human tissue as a result of the current transport process if the skin areas previously treated with aluminium chloride are treated with LWI at the same time.