Written and maintained by CASRAI Editorial Board
Last updated
General information only, not medical advice. Device selection and use belong with a qualified clinician and the manufacturer’s instructions for use.
Short answer
Microcurrent therapy is a non-invasive electrical modality that delivers subsensory currents, typically in the microampere range, with the aim of supporting tissue repair. A 2025 narrative review contrasts it with TENS, which works in the milliampere range, about 1,000 times higher. The same review says more high-quality evidence is needed.
Definition and scope
Jonik, Rothka and Cherin (2025) describe microcurrent (MIC) therapy as a non-invasive treatment modality that emits subsensory electrical currents, typically delivered in the microampere range. Subsensory means the user is not meant to feel the current. The review covers uses discussed in the literature for chronic pain, wound healing, musculoskeletal injuries and neuropsychological conditions. This page explains the modality and how it is told apart from related devices; it does not describe treatment settings or protocols.
In short, what is microcurrent? A low-intensity electrical current, below the level of sensation, as opposed to the stronger currents used in nerve or muscle stimulation.
How microcurrent differs from TENS and muscle stimulators
The three terms are often mixed up.
| Device family | What the source says | Source |
|---|---|---|
| Microcurrent (MIC) | Subsensory currents, typically in the microampere range; the review says the low intensity avoids nerve depolarization, muscle contraction, fatigue and pain. | Jonik et al., 2025 |
| TENS | Currents in the milliampere range, which the review puts at 1,000 times higher than MIC, resulting in nerve depolarization, muscle contraction, fatigue and pain. | Jonik et al., 2025 |
| Powered muscle stimulator | Defined in 21 CFR 890.5850 as an electrically powered device for medical purposes that repeatedly contracts muscles by passing electrical currents through electrodes contacting the affected body area. Class II. | 21 CFR 890.5850 |
For readers who handle TENS or EMS supplies, see our guides to what a TENS unit is, how a TENS unit works, TENS pads and EMS pads.
Proposed mechanisms
The review lists several mechanisms as proposed rather than established: restored transmembrane potential, calcium influx, ATP synthesis, activation of fibroblasts and satellite cells, and endothelial nitric oxide release with angiogenesis. It states that the exact mode of action is unclear and that microcurrent is presumed to follow the Arndt-Schultz law, in which low currents stimulate and high currents inhibit. A study it cites reported that a 500 μA current increased ATP production by 500% while a 5 mA current inhibited it. That is a laboratory finding about a mechanism, not a statement about outcomes in people.
Cranial electrotherapy stimulation (CES) is described in the review as microcurrent applied through earclip electrodes.
What the evidence shows
- The source is a narrative review, not a systematic review, and its authors write that more high-quality evidence is needed.
- The review discusses CES and wound care as areas of study and reports that some of its data are inconsistent. This page does not assess whether microcurrent works for any condition.
- The review notes that small samples, limited controls and varied parameters make it hard to set standard dosing across studies.
Where it matters for labs, clinics and supply decisions
The marketing term “microcurrent” does not decide how a device is regulated. Under 21 CFR 890.5850 a powered muscle stimulator is defined by repeatedly contracting muscles, which the review says microcurrent avoids, so that regulation should not be assumed to cover a microcurrent device. FDA classification runs through the device’s product code and cleared indication. The FDA Product Classification database shows the pattern: product code NUW, “stimulator, muscle, powered, dental”, sits under 890.5850 as Class 2 with the cleared indication “Relief of muscle spasms associated with tmj. Muscle reeducation, increasing blood flow.” A checklist for staff reading a device record:
- Find the cleared indication in the FDA record, not the brochure wording.
- Note the product code and the regulation number attached to it.
- Note the device class listed for that code.
- Read the manufacturer’s instructions for use for intended users and settings.
Common misunderstandings
- Microcurrent is a stronger TENS. The review places it at about one-thousandth of TENS intensity.
- Microcurrent is a muscle stimulator. The regulation describes muscle stimulators as devices that repeatedly contract muscles; the review says microcurrent avoids muscle contraction.
- The ATP figures prove clinical benefit. The review presents the mechanisms as proposed and the mode of action as unclear.
FAQ
What is microcurrent?
Microcurrent is a low-intensity, subsensory electrical current, typically in the microampere range, used in a non-invasive therapy modality (Jonik et al., 2025).
How is microcurrent different from TENS?
TENS uses milliampere currents, about 1,000 times higher, which the review links to nerve depolarization and muscle contraction. Microcurrent stays below the level of sensation.
Is microcurrent therapy proven?
The 2025 narrative review is a summary of the literature, not a systematic review. Its authors state that more high-quality evidence is needed, and this page does not judge whether microcurrent works for any condition.
Sources
- Jonik S, Rothka AJ, Cherin N. Investigating the therapeutic efficacy of microcurrent therapy: a narrative review. Therapeutic Advances in Chronic Disease. 2025;16:20406223251361677. https://pmc.ncbi.nlm.nih.gov/articles/PMC12357078/. Checked 30 October 2026.
- 21 CFR 890.5850, Powered muscle stimulator. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-890/subpart-F/section-890.5850. Checked 30 October 2026.
- FDA Product Classification database, product code NUW. https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfTPLC/tplc.cfm?id=NUW. Checked 30 October 2026.
