SHUNT® technology is the patented treatment-termination system used in the ACTIVApatch family of wearable iontophoresis patches. It allows the patch to automatically turn down or stop its therapeutic current after the intended electrical treatment has been completed.
This built-in technology eliminates the need for a patient to manually switch off a controller at the end of treatment. It also allows ACTIVApatch to provide a self-contained treatment without an external dose controller, lead wires, charging station, or separate battery pack.
Patented shut-off technology for all three ACTIVApatch models:
- IntelliDose™ 2.5
- IontoGo™ 4.0
- IontoGo™ 12.0
IntelliDose 2.5 combines the shut-off feature with a microprocessor and SmartPower™ LED feedback. The IontoGo models use a simpler self-powered design without an LED status display.
Compare all three options on our ACTIVApatch product page.
SHUNT Technology at a Glance
| Question | Answer |
|---|---|
| What does SHUNT technology do? | Automatically turns down or ends current after the intended electrical treatment is complete |
| What treatment quantity does it control? | Electrical dose, measured in milliamp-minutes or mA-min |
| Does it measure medication in the tissue? | No |
| Does it measure pain relief or clinical results? | No |
| Is an external controller required? | No |
| Is a timer required from the patient? | Patients should still follow the prescribed removal time and device instructions |
| Which ACTIVApatch models use patented shut-off technology? | Current manufacturer materials list: IntelliDose 2.5, IontoGo 4.0, and IontoGo 12.0 |
| Which model also provides LED feedback? | IntelliDose 2.5 |
| Does SHUNT replace the need for correct application? | No |
| Can the patch remain attached indefinitely after completion? | No, remove it according to the model-specific instructions |
What Is a Shunt?
In electrical engineering, a shunt is an alternate pathway through which electrical current can be diverted. A shunt resistor is a component used to control, redirect, limit, or monitor current within a circuit.
In an ACTIVApatch, SHUNT technology is incorporated into the patch’s internal electrical design. After the intended treatment capacity has been used, the system redirects or reduces current so that the therapeutic current through the patient no longer continues at its previous level.
The full proprietary circuit schematic is not provided in the public instructions. It is therefore more accurate to describe SHUNT as an internal current-diversion and treatment-termination system than as a mechanical switch that simply opens the circuit.
Simplified Conceptual Flow
During treatment:
Built-in power source → drug reservoir → patient’s skin → dispersive electrode → completed treatment circuit
At treatment completion:
Preset electrical capacity reached → SHUNT termination mechanism engages → The therapeutic current is turned down or stopped. → The patch is removed according to instructions
This diagram is a simplified functional explanation, not the manufacturer’s exact proprietary circuit.
What Does SHUNT Technology Measure?
SHUNT technology is associated with the completion of the patch’s electrical iontophoresis dose, measured in milliamp-minutes.
The basic relationship is
Electrical dose = current in milliamps × treatment time in minutes
For example:
| Average current | Time | Electrical dose |
|---|---|---|
| 1 mA | 80 minutes | 80 mA-min |
| 0.5 mA | 160 minutes | 80 mA-min |
| 0.33 mA | Approximately 240 minutes | Approximately 80 mA-min |
| 0.11 mA | Approximately 720 minutes | Approximately 80 mA-min |
These examples illustrate the mathematical relationship only. They are not instructions for programming or modifying an ACTIVApatch.
ACTIVApatch models use different current-and-time profiles to reach their labeled treatment capacity. IntelliDose 2.5 delivers 80 mA-min in approximately 2.5 hours, IontoGo 4.0 in approximately four hours, and IontoGo 12.0 in approximately 12 hours.
Electrical Dose Is Not the Same as Medication Dose
An 80 mA-min rating describes the electrical charge delivered by the iontophoresis system. It does not mean:
- 80 milligrams of medication
- 80 milliliters of medication
- A guaranteed quantity of medication in the tendon or other tissue
- A measurement of medication absorbed into the bloodstream
- A measurement of clinical effectiveness
The patch controls the electrical treatment. The amount of medication transported through the skin can vary according to the following:
- Medication identity and formulation
- Ionic charge
- Medication concentration
- Molecular size
- Competing ions
- Skin resistance
- Skin hydration
- Treatment location
- Reservoir preparation
- Patch contact
- Individual patient physiology
SHUNT technology should therefore be described as supporting controlled electrical-dose termination, not as directly measuring drug molecules in the tissue.
Important Terminology
| Term | What it means |
|---|---|
| 80 mA-min | Electrical iontophoresis dose |
| 2.0 cc | Volume used to hydrate the drug reservoir |
| Medication concentration | Quantity of medication per unit of solution |
| Medication loaded | Amount placed in the patch reservoir |
| Medication transported | A portion moved through the skin |
| Tissue concentration | Medication measured at a particular tissue location |
| Systemic exposure | Medication that reaches the bloodstream |
| SHUNT completion | End of the patch’s intended electrical treatment |
How ACTIVApatch Begins Treatment
The current ACTIVApatch designs use a pull-tab activation process.
A typical clinician-directed setup includes:
- Inspecting the patch and treatment area.
- Confirming that the skin is intact and dry.
- Preparing the active reservoir with the prescribed ionic solution.
- Removing the battery pull tab to activate the patch.
- Removing the release liner.
- Applying the patch to the prescribed treatment area.
- Allowing the self-contained electrical system to deliver the treatment.
- Removing and disposing of the patch after the model-specific treatment time.
The IontoGo 4.0 and 12.0 instructions specify a 2.0 cc reservoir fill and state that these patches are intended for negatively charged ionic medication. The patches do not require saline because their dispersive hydrogel is already designed to complete the return side of the circuit.
ACTIVApatch Uses a No-Saline Design
| Component | Function |
|---|---|
| Active reservoir | Holds the prescribed negatively charged ionic solution |
| Hydrogel dispersive electrode | Completes the circuit without separately added saline |
| Built-in power source | Produces the voltage required for current flow |
| Pull tab | Activates the patch’s power system |
| SHUNT technology | Terminates or turns down treatment current at completion |
| Adhesive backing | Maintains skin contact |
| SmartPower LED | Provides status feedback on IntelliDose 2.5 only |
Its hydrogel dispersive technology reduces preparation steps and eliminates errors associated with adding saline to the wrong section or adding too much solution.
Does ACTIVApatch Work With Positive and Negative Medication?
The IontoGo instructions describe the 4.0 and 12.0 models as systems for negatively charged ionic medication. The IntelliDose instructions likewise identify negatively charged ionic medication. These products should therefore not be described as user-selectable positive-or-negative systems unless a current model-specific instruction document expressly supports that use.
This is different from certain two-reservoir iontophoresis systems that allow the clinician to choose a positive or negative medication chamber.
| System design | Medication-polarity workflow |
|---|---|
| Current ACTIVApatch models | Manufacturer instructions identify negatively charged ionic medication |
| IontoPatch two-chamber designs | Medication may be placed in the chamber matching its polarity |
| Wired iontophoresis systems | Polarity depends on controller leads and selected drug electrodes. |
| Unknown medication charge | Must be confirmed before treatment |
How SHUNT Technology Ends Treatment
Once activated and correctly applied, the patch begins delivering low-level direct current. The current continues over the model’s intended treatment period.
At the completion point:
- The intended electrical capacity has been reached.
- The SHUNT system turns down or terminates the therapeutic output.
- Treatment does not continue indefinitely at the original current level.
- The patient removes the patch according to the instructions.
- The single-use patch is discarded.
This feature is helping prevent treatment from continuing beyond the preset electrical dose.
What SHUNT Does and Does Not Do
| SHUNT does | SHUNT does not |
|---|---|
| Controls treatment termination | Diagnose the condition |
| Helps stop current after the preset electrical treatment | Measure pain relief |
| Operates without an external controller | Measure medication concentration in tissue |
| Supports predictable mA-min completion | Confirm that the medication was correctly selected |
| Reduces dependence on manual timing for electrical shutoff | Correct improper reservoir filling |
| Helps prevent continued full-current operation | Detect every form of poor adhesion |
| Works within a single-use patch | Replace clinician supervision or instructions |
Does SHUNT Eliminate the Need to Track Wear Time?
No. Automatic electrical termination does not mean the patch should be left attached indefinitely.
The model-specific instructions tell the patient when to remove it:
| Model | Labeled treatment format | Removal guidance |
|---|---|---|
| IntelliDose 2.5 | 40 mA-min in approximately 1.25 hours or 80 mA-min in approximately 2.5 hours | Follow LED patterns and clinician instructions |
| IontoGo 4.0 | 80 mA-min over approximately four hours | Remove after approximately four hours |
| IontoGo 12.0 | 80 mA-min over approximately 12 hours | Remove after approximately 12 hours |
The IontoGo instructions specifically direct the clinician to instruct the patient to remove the 4.0 patch after four hours and the 12.0 patch after 12 hours.
Patients should not assume that automatic shutoff makes extended skin contact harmless. Leaving an adhesive medical device attached longer than directed can increase exposure to:
- Adhesive irritation
- Moisture accumulation
- Pressure
- Friction
- Medication residue
- Skin discoloration
- Difficulty during removal
SHUNT vs. SmartPower: What Is the Difference?
SHUNT® and SmartPower™ are related ACTIVApatch technologies, but they do different jobs.
| Feature | SHUNT® technology | SmartPower™ LED feedback |
|---|---|---|
| Primary purpose | Treatment termination | Visible treatment-status information |
| Found on | The manufacturer lists materials across all three ACTIVApatch models | IntelliDose 2.5 |
| The user sees it operating | Usually not. | Yes, through LED flash patterns |
| Ends treatment | Yes | Indicates status; the underlying patch technology ends treatment |
| Monitors skin resistance | Not described as its primary function | IntelliDose microprocessor evaluates resistance |
| Identifies high resistance | No visible alert by itself | Yes |
| Indicates first 40 mA-min completion | No visible indication on IontoGo | Yes |
| Indicates 80 mA-min completion | Automatic electrical termination | LED turns off at completion |
| Requires an external controller | No | No |
Learn more in our Guide to SmartPower LED Feedback.
How IntelliDose 2.5 Uses SHUNT and SmartPower Together
IntelliDose 2.5 is the most electronically sophisticated ACTIVApatch model. It combines:
- A self-contained power source
- An intelligent microprocessor
- Skin-resistance monitoring
- SmartPower LED status patterns
- 40 or 80 mA-min treatment options
- Patented treatment shutoff
- No-saline hydrogel dispersive technology
During the first portion of treatment, the LED flashes once every 30 seconds. A short-long-short sequence identifies completion of the first 40 mA-min stage. If the patch remains in place, it proceeds into a second treatment stage, indicated by two flashes every 30 seconds. The LED turns off after the full 80 mA-min treatment.
IntelliDose LED Summary
| LED pattern | Meaning |
|---|---|
| Once every 30 seconds | The first 40 mA-min treatment is underway |
| Short-long-short for approximately three minutes | The first 40 mA-min treatment has been completed |
| Twice every 30 seconds | The second 40 mA-min stage is underway |
| Three flashes every 10 seconds | Skin resistance is above the acceptable range |
| LED turns off after full treatment | The 80 mA-min treatment is complete |
If acceptable skin resistance is not established within the instructed period, the manufacturer recommends considering a wired system such as the ActivaDose II Iontophoresis Controller with an appropriate electrode system.
IontoGo 4.0 vs. IontoGo 12.0
Both IontoGo models use a self-contained, no-saline, single-use patch design and deliver a labeled 80 mA-min electrical treatment. The main difference is the treatment rate and wear time.
| Feature | IontoGo 4.0 | IontoGo 12.0 |
|---|---|---|
| Electrical dose | 80 mA-min | 80 mA-min |
| Approximate treatment time | 4 hours | 12 hours |
| Drug-reservoir fill volume | 2.0 cc | 2.0 cc |
| Active area | 11.4 cm² | 11.4 cm² |
| Saline required | No | No |
| External controller | No | No |
| SHUNT shutoff | Yes | Yes |
| SmartPower LED | No | No |
| Microprocessor feedback | No | No |
| Medication polarity in current IFU | Negatively charged | Negatively charged |
| Primary distinction | Shorter wear period | Slower, extended-wear delivery |
Both products use the same broad technology, but IontoGo 4.0 delivers the electrical treatment at a higher average rate over a shorter period. IontoGo 12.0 spreads the same labeled electrical dose over approximately three times as long.
See our IontoGo 4-Hour vs. 12-Hour Comparison for additional scheduling considerations.
ACTIVApatch Model Comparison
| Feature | IntelliDose 2.5 | IontoGo 4.0 | IontoGo 12.0 |
|---|---|---|---|
| Treatment capacity | 40 or 80 mA-min | 80 mA-min | 80 mA-min |
| Approximate time | 1.25 or 2.5 hours | 4 hours | 12 hours |
| Built-in power | Yes | Yes | Yes |
| Patented shutoff technology | Yes | Yes | Yes |
| SmartPower LED | Yes | No | No |
| Intelligent microprocessor | Yes | No | No |
| Skin-resistance alert | Yes | No visible alert | |
| Saline required | No | No | No |
| Fill volume | Up to 2.0 cc | 2.0 cc | 2.0 cc |
| External wires | No | No | No |
| External controller | No | No | No |
| Single-use | Yes | Yes | Yes |
| Best fit | Fast treatment and visible feedback | Four-hour mobile treatment | Extended 12-hour treatment |
The patented shut-off technology is on all three models, while limiting intelligent microprocessor feedback and SmartPower LED functions to the IntelliDose 2.5.
SHUNT Technology vs. Electrode-Depletion Shutoff
Different wearable iontophoresis systems can end electrical delivery through different internal mechanisms.
ACTIVApatch uses its patented shut-off design. By comparison, the IontoPatch family relies on controlled electrode coatings that are consumed during treatment. When those coatings are depleted, current substantially declines or is suspended.
| Feature | ACTIVApatch SHUNT system | IontoPatch coating-depletion system |
|---|---|---|
| Treatment termination | Internal patented shut-off or turn-down technology | Current declines when controlled electrode coatings are depleted |
| No external controller | Yes | Yes |
| Built-in power source | Yes | Yes |
| Saline required | No for current ACTIVApatch models | Yes for current IontoPatch application workflow |
| Drug-reservoir design | Active medication reservoir plus prehydrated dispersive hydrogel | Positive and negative chambers |
| Medication polarity | Current ACTIVApatch IFUs identify negatively charged solutions | A positive or negative chamber can be selected according to medication polarity |
| Status LED | IntelliDose only | No |
| Main dose options | 40 or 80 mA-min | 80 or 120 mA-min |
| Typical current models | IntelliDose 2.5, IontoGo 4.0, IontoGo 12.0 | IontoPATCH STAT, IontoPATCH 80, Extra Strength |
Review our IontoPatch vs. ACTIVApatch comparison for a broader comparison of treatment times, fill volumes, activation methods, and patch selection.
SHUNT Technology vs. a Wired Dose Controller
A reusable wired controller also ends treatment after a programmed electrical dose, but it does so using a separate electronic unit.
| Feature | ACTIVApatch with SHUNT | Wired iontophoresis controller |
|---|---|---|
| External machine | No | Yes |
| Lead wires | No | Yes |
| Separate electrodes | Integrated into patch | Required |
| Current adjustment during treatment | Preset by patch design | Clinician adjustable |
| Dose selection | Determined by model | Programmed on controller |
| Live display | IntelliDose LED only | Usually current, time, or dose display |
| Skin-resistance feedback | IntelliDose only | Controller-dependent |
| Patient mobility | High | Limited while connected |
| Treatment supervision | May continue outside clinic when directed | Commonly supervised in clinic |
| Reusable equipment | No | The controller is reusable |
| Treatment termination | Built into patch | Controlled electronically by external unit |
A wired system such as the ActivaDose II may be preferable when direct current adjustment, a shorter supervised session, or real-time treatment monitoring is required. It can be paired with a delivery system such as Trivarion iontophoresis electrodes.
Why Automatic Treatment Termination Matters
An automatic treatment endpoint can support clinical workflow in several ways.
More Predictable Electrical Dosing
The system is designed around a defined mA-min capacity rather than relying only on the patient to estimate when sufficient current has flowed.
Fewer External Components
No separate machine, cable, charging station, or battery pack must remain attached to the patient.
Improved Mobility
The patient can remain mobile during the prescribed treatment, subject to the application instructions and clinical restrictions.
Reduced Dependence on Manual Shutoff
The patient does not have to operate a controller when the electrical treatment reaches completion.
Standardized Workflow
The clinician selects the appropriate ACTIVApatch model according to dose and treatment time rather than programming a different current and timer for each application.
These advantages do not eliminate the need for correct medication selection, reservoir filling, skin preparation, placement, patient education, and removal timing.
Common Misconceptions About SHUNT Technology
“SHUNT measures exactly how much medication enters the body.”
It does not. It controls or terminates the electrical mA-min treatment. Medication transport remains influenced by the drug formulation, concentration, skin, contact quality, and other factors.
“The patch knows when the patient has received enough clinical benefit.”
It does not measure pain, inflammation, tissue response, or treatment success.
“SHUNT means the patient can wear the patch indefinitely.”
No. The patch should be removed after the specified treatment period.
“SHUNT and SmartPower are the same technology.”
No. SHUNT ends the electrical treatment. SmartPower provides visible status and impedance feedback on IntelliDose 2.5.
“Only the IontoGo models have shutoff technology.”
Patented shut-off technology for IntelliDose 2.5 as well as IontoGo 4.0 and 12.0.
“IontoGo can be loaded with any positive or negative medication.”
The IontoGo instructions specify negatively charged ionic medication. Medication suitability, formulation, polarity, concentration, and prescription must be confirmed before treatment.
“Automatic shutoff prevents every skin reaction.”
No. Iontophoresis can still cause redness, irritation, discomfort, burns, histamine reactions, adhesive reactions, or medication-related effects. Patients must follow all skin-preparation and monitoring instructions.
Application and Safety Considerations
The presence of automatic shutoff does not replace basic iontophoresis precautions.
| Consideration | Guidance |
|---|---|
| Prescription | Use only by or on the order of an appropriately licensed healthcare professional |
| Medication | Confirm the exact medication, formulation, concentration, and polarity |
| Current IontoGo polarity | Use only an appropriate negatively charged ionic solution as specified in the IFU |
| Fill volume | Follow the model-specific instructions; IontoGo lists 2.0 cc |
| Underfilling | Can leave dry areas in the reservoir |
| Overfilling | Can cause leakage and poor current distribution |
| Skin | Apply only to intact, dry skin |
| Hair | Clip when necessary; do not shave immediately before treatment |
| Creams and oils | Avoid on the treatment area before application |
| Pressure | Do not lean against, bind, tape, or compress the patch |
| Weight-bearing areas | Current IontoGo instructions advise against placement on weight-bearing surfaces |
| Water | Do not get the electrode wet |
| MRI | Remove before MRI |
| Metal | Keep jewelry and metallic objects away from the electrodes |
| Discomfort | Remove immediately and report burning or discomfort |
| Reuse | Single-use only |
| Removal | Follow the model-specific treatment time even with automatic shutoff |
The IontoGo instructions warn that poor contact, excessive movement, compression, or improper reservoir preparation can cause uneven current distribution and increase the risk of irritation.
Frequently Asked Questions
What is SHUNT technology?
SHUNT is ACTIVApatch’s patented electrical treatment-termination technology. It automatically turns down or stops the therapeutic current after the intended mA-min treatment is complete.
Does SHUNT technology measure the medication dose?
It controls the electrical mA-min treatment. It does not directly measure the number of medication molecules transported through the skin or the tissue concentration reached.
What does "80 mA-min" mean?
It is an electrical iontophoresis dose equal to current in milliamps multiplied by treatment time in minutes. It does not mean 80 mg of medication.
Does IntelliDose 2.5 use SHUNT technology?
Comparisons list patented shut-off technology for IntelliDose 2.5, IontoGo 4.0, and IontoGo 12.0. IntelliDose also adds a microprocessor and SmartPower LED.
What is the difference between SHUNT and SmartPower?
SHUNT ends the electrical treatment. SmartPower is the LED feedback system that reports treatment stages and skin-resistance conditions on IntelliDose 2.5.
Does IontoGo 4.0 shut off after four hours?
It is designed to complete its labeled 80 mA-min treatment over approximately four hours and uses automatic shutoff technology. The instructions direct the patient to remove it after four hours.
Does IontoGo 12.0 shut off after 12 hours?
It is designed to complete its labeled 80 mA-min treatment over approximately 12 hours and uses automatic shutoff technology. The instructions direct the patient to remove it after 12 hours.
Do ACTIVApatch products need saline?
The current IntelliDose and IontoGo models use hydrogel dispersive technology and do not require separate saline activation.
How much medication solution is placed in the patch?
Current manufacturer specifications list a drug-reservoir fill volume of up to 2.0 cc. The clinician must follow the specific product instructions and prescription.
Can IontoGo deliver positively charged medication?
IontoGo instructions specify negatively charged ionic medications. It should not be represented as a dual-polarity patch without supporting model-specific manufacturer instructions.
Can the patient feel when SHUNT activates?
The IontoGo models do not provide a visible or audible completion signal. IntelliDose uses its LED to show treatment stages and turns the LED off when the full treatment is complete.
Can I leave the patch on after it shuts off?
Remove it according to the model-specific treatment instructions. Automatic current termination does not authorize unlimited adhesive contact.
Does automatic shutoff prevent burns?
It may help prevent continued full-current treatment beyond the intended electrical dose, but it cannot eliminate all risks. Improper filling, poor contact, damaged skin, pressure, movement, medication sensitivity, or other factors may still produce irritation or burns.
Which ACTIVApatch should I choose?
- Choose IntelliDose 2.5 when fast delivery and visible feedback are priorities.
- Choose IontoGo 4.0 for an 80 mA-min treatment over approximately four hours.
- Choose IontoGo 12.0 for a slower 80 mA-min treatment over approximately 12 hours.
The clinician should base the choice on the prescribed electrical dose, medication, patient skin tolerance, treatment location, and schedule.
The Bottom Line
SHUNT® technology is ACTIVApatch’s built-in method for automatically ending the electrical iontophoresis treatment. It helps a self-contained patch deliver a defined mA-min capacity without an external dose controller or manual shutoff.
SHUNT technology automatically turns down or terminates ACTIVApatch current after the preset electrical iontophoresis treatment has been completed.
It should not be described as measuring the exact quantity of medication entering the tissue or guaranteeing a particular clinical result.
- IntelliDose 2.5, which adds microprocessor control and SmartPower LED feedback
- IontoGo 4.0, which delivers 80 mA-min in approximately four hours
- IontoGo 12.0, which delivers 80 mA-min in approximately 12 hours
Explore the complete ACTIVApatch family at Balego, compare IontoGo 4.0 and IontoGo 12.0, or browse our full collection of iontophoresis patches, controllers, and electrodes.
Medical and Professional-Use Notice
ACTIVApatch products are intended for professional, clinician-directed iontophoresis. Medication selection, formulation, concentration, electrical polarity, dose, treatment site, patch model, application method, treatment time, and frequency should be determined by an appropriately licensed healthcare professional.
Automatic electrical shutoff does not replace the complete manufacturer instructions, medication labeling, patient screening, skin inspection, monitoring, or clinical judgment.
Suggested Image Alt Text
- ACTIVApatch internal current path and shutoff diagram
- SHUNT technology versus SmartPower LED feedback
- IntelliDose 2.5, IontoGo 4.0, and IontoGo 12.0 comparison
- IontoGo 4.0 automatic four-hour treatment shutoff
- IontoGo 12.0 extended-wear iontophoresis patch
- Difference between electrical dose and medication dose
- ACTIVApatch versus wired iontophoresis controller
- ACTIVApatch SHUNT versus IontoPatch coating depletion
