If you have seen pulsed electromagnetic field devices described as FDA-cleared for healing bones, the description was wrong for most of their history. The first such device was approved in November 1979 through premarket approval, the Food and Drug Administration’s most demanding route, reserved for the highest-risk Class III devices. They stayed there until a final order published on April 16, 2026, moved them to Class II, where new versions can reach the market through a lighter process called clearance.
The correction matters because it shows something the rest of this market blurs. Electromagnetic energy is real medicine in a few narrow, regulated places: bones that will not knit, depression that has not responded to medication, swelling after surgery. Around those places sits a trade in frequency generators, quantum pendants and radiation shields whose documented record is mostly warning letters, prosecutions and laboratory tests. The harms on that record are concrete: pendants and bracelets that give off low-level radiation, and a newspaper’s count of at least four deaths among people who gave up conventional treatment for frequency machines.
This article separates the two. Its subject is electromagnetic fields, inaudible signals and electronic devices sold on the word frequency. Sound you can hear, from gongs to tuned recordings, belongs to the companion piece on sound healing.
Bone stimulators were approved in 1979 and reclassified in 2026
Two FDA terms carry the story. Premarket approval means the maker submits its own evidence of safety and effectiveness for agency review. Clearance, through a filing called a 510(k), rests on showing a device is substantially equivalent to one already sold; the acupressure and supplement-oversight reports on this site go further into what a clearance does and does not establish.
At a September 2020 advisory panel meeting, FDA staff described noninvasive bone growth stimulators as Class III devices subject to premarket approval. The first, a pulsed electromagnetic field system for the limbs, was approved on November 6, 1979. Approved uses listed for the category included established nonunion after trauma, some fresh fractures, a rare congenital bone defect, and use alongside spinal fusion surgery in the neck or lower back. Four technologies were in play: capacitive coupling, pulsed electromagnetic fields, combined magnetic fields and low-intensity pulsed ultrasound.
The April 2026 order created a new regulation, 21 CFR 890.5870. It defines the device as a prescription product that stimulates bone through electrical, magnetic or ultrasonic fields, used alongside fracture fixation and spinal fusion or to treat established nonunions and failed fusions. Its special controls, the device-specific requirements that come with Class II, call for clinical data including imaging that shows fusion at the treated site. They also require testing that keeps signal characteristics within safe physiologic limits, and labeling that warns about burns, shock, skin irritation and implanted devices. A regulated stimulator, in other words, has to document exactly what signal it delivers.
The change was slow. A petition asked FDA to reclassify the stimulators in 2005, and an advisory panel that met in June 2006 recommended keeping them in Class III. The petitioner later withdrew the request, and FDA closed the matter. The 2020 panel reopened the question, and the final order, effective 30 days after publication, arrived about 21 years after that first petition.
Whether the stimulators speed healing is less settled than their regulatory history suggests. A 2011 Cochrane review found four randomized, placebo-controlled trials with 125 people, most with nonunion of the shinbone. The pooled risk ratio for healing was 1.96, with a range from 0.86 to 4.48 that crosses no effect. Two trials found no reduction in pain, none measured function, and the reviewers called the evidence inconclusive and insufficient to guide practice.
A 2020 meta-analysis in Bioelectromagnetics, from West China Hospital at Sichuan University, gathered 22 sham-controlled trials with 1,468 participants. In the 14 trials that reported healing rates, 79.7 percent of fractures healed with stimulation against 64.3 percent with sham. The authors rated that evidence moderate in quality, found moderate-quality evidence of less fracture pain, and rated the evidence on faster healing very low. In this library’s terms, bone healing sits at positive trial evidence, contested interpretation: the newer analysis finds a benefit at moderate certainty, and the older Cochrane review found too little to judge.
Two more electromagnetic treatments with federal standing
Repetitive transcranial magnetic stimulation, or rTMS, uses an external device to deliver pulsed magnetic fields to the prefrontal cortex, the front of the brain. FDA placed it in Class II through an order issued on October 7, 2008, and a July 2011 rule wrote that classification into federal regulations, for major depressive disorder in patients who have not improved on at least one antidepressant. A January 2023 fact sheet from the National Center for Complementary and Integrative Health lists severe migraine and obsessive-compulsive disorder among other FDA-authorized uses and treats the method as conventional medicine.
The second is less familiar. Nonthermal shortwave therapy is a prescription device that delivers pulsed electromagnetic energy at 13.56 or 27.12 megahertz, without producing deep heat, for adjunctive treatment of pain and swelling in soft tissue after surgery. It has been Class II since a 2015 reclassification. Its heat-producing relative, shortwave diathermy, carries an explicit exclusion in the same regulation: not for treating cancer.
NCCIH’s fact sheet also reports the pain research on pulsed fields plainly. Reviews it summarizes found benefit for general musculoskeletal pain (a 2020 review of 21 studies with 1,101 participants), for knee and hand osteoarthritis, and for chronic low back pain (a 2022 review of 14 studies with 618 participants). Studies of shoulder pain and of nerve pain from chemotherapy found no benefit. It judges electromagnetic therapies apparently safe for treating pain. The same sheet says research does not conclusively support static magnets, the kind sold in bracelets and braces, for pain.
What the legitimate therapies share is the useful part. Each has a prescription requirement, a named condition, a regulation number and a defined physical dose, a specific field or frequency band aimed at specific tissue. That is the checklist the rest of this article measures products against.
Frequency generators and the enforcement record
Frequency itself is not mysterious. It is the number of times per second a wave or current repeats, measured in hertz, and everything from household current to radio has one. The shortwave device above runs at 13.56 million cycles per second. A frequency on its own is a description, not a treatment; what matters is how much energy is delivered, to which tissue, with what measured effect.
At the other end of this market are boxes that send small currents or signals through the body at programmed frequencies, sold on the claim that the right frequency destroys disease. Sellers have called them Rife machines, or used words such as bioresonance and scalar.
FDA’s device center laid out a recent example in a warning letter dated November 18, 2022. The firm sold a bioresonance ultrasound generator, a smartwatch analyzer, a water restructuring pad, therapy balls said to apply frequency to painful areas, and an app. Its website advertised a cancer treatment with a 90 percent success rate, including stage 3 and stage 4 disease, along with claims for diabetes, Alzheimer’s disease, kidney and liver disease, stroke and depression. Programs in the app, the letter noted, were offered for conditions as different as Parkinson’s disease, glaucoma, scoliosis and addiction.
FDA called the products adulterated, because they lacked premarket approval, and misbranded, because the firm had neither notified the agency through a 510(k) nor registered and listed them. The letter also cited the firm for denying or limiting an FDA inspection. The logic is worth knowing. Under federal law, what a product is sold to do decides whether it is a medical device, so a box marketed to treat cancer is regulated as one whatever is inside it.
The criminal cases below come from news coverage, not court records. In February 2010, Courthouse News Service and NBC San Diego reported that a San Diego man was sentenced to 51 months in prison after conviction on 26 felony counts of selling unapproved devices. Prosecutors described them as micro-current frequency generators, which he claimed treated everything from AIDS and diabetes to strokes and worms. Some of the sales happened while he was on pretrial release.
In October 2015, the Times of San Diego reported that a Huntington Beach man received 18 months, a $3,000 fine and a $30,000 forfeiture. He had sold hundreds of devices described as Rife machines at $750 each, marketed for AIDS, diabetes, strokes and ulcers. FDA had warned him in 2010.
The harm these devices can cause is mostly indirect. A 2000 investigation by the Sydney Morning Herald counted at least four people in Australia and New Zealand, including a 5-year-old, who died after giving up conventional treatment for such machines. The count was the newspaper’s own, not an official tally.
Electronics Australia, the paper reported, opened one device and found a nine-volt battery, wiring, a switch, a timer and two short lengths of copper tubing, about $15 of parts. Australia’s Therapeutic Goods Administration told the paper the machine had been listed, a registration step, without ever being tested for effectiveness, and that the listing had since been cancelled. It is the same gap that separates registration from approval in the United States, discussed below. Why people choose to set treatment aside, and what that choice costs, is the subject of the substitution report in this series.
Controlled tests are scarce, and the best one is negative. In a 1997 double-blind trial at a children’s hospital in Davos, Switzerland, 32 children with long-lasting eczema received hospital care plus either an active or a sham bioresonance treatment. Both groups improved, and the device added no measurable effect. A 2014 placebo-controlled pilot in 190 smokers in Istanbul reported higher quit rates with an active bioresonance device, a single pilot result that still needs confirmation. For the central claim, that a programmed frequency cures cancer or infection, the status is insufficient evidence to assess in the untested sense: this library found no controlled trial of it at all.
Radioactive negative ion jewelry, at its true size
The best-documented physical hazard in this market is radiation from products that promise wellness through invisible energy. It is real, and it is small.
On December 16, 2021, the Netherlands’ Authority for Nuclear Safety and Radiation Protection warned the public about products that emit ionizing radiation. Its notice says the agency knows of ten such products, then lists nine: a sleep mask, necklaces, five bracelets including one marketed for children, and a pendant sold as a quantum pendant. The national public health institute, RIVM, did the testing. The authority stated that “the level of radiation measured is low and risk of health problems is low too.”
The concern is cumulative skin exposure. Worn 24 hours a day for a year, the authority said, some items could exceed the strict Dutch limit for skin dose. Dutch law bans their sale under the Nuclear Energy Act. Owners were told to stop wearing them, store them sealed in a closed cabinet, await return instructions, and keep them out of household trash. Only the notice’s title mentions an anti-5G pendant; its text describes the products as negative ion items.
American state agencies reached similar findings earlier, and they explain where the radiation comes from. In May 2018 the Illinois Emergency Management Agency, in a release republished by a local newspaper, said a pendant sold as a quantum or scalar energy pendant contained thorium and uranium. It traced them to volcanic rock or monazite sands. The agency saw no immediate health concern but said continuous wear could slightly raise skin exposure, and it suggested wearing the pendants over clothing. It and the US Nuclear Regulatory Commission had found that some contained enough radioactive material to warrant increased regulatory controls.
Utah’s Division of Waste Management and Radiation Control says negative ion technology can rely on minerals containing thorium or uranium. Its page reports that the NRC found some such wristbands may be subject to radioactive materials licensing and recommends that concerned users stop wearing them, and that FDA judged them no significant public health concern. NRC testing of older wristband models found radiation in the range of upper natural background levels, and Utah says the current versions it describes fall below licensing thresholds. Utah also says such items can safely go in the trash, the opposite of the Dutch advice.
Washington State’s health department found unacceptable levels of radioactive material in some products tested, sold with claims of negative ions, quantum scalar energy and volcanic lava energy, and calls thorium and uranium both radioactive and chemically toxic. Some items it tested had very low radioactivity; others had enough to require a radioactive materials license in the state. Short-term exposure, the department says, poses no immediate health threat.
Read together: low-level radiation, mainly a skin-dose concern with long, close contact, illegal to sell in the Netherlands, potentially subject to licensing in the United States, with disposal rules that depend on where you live.
Shields against phones and 5G
A related product line promises to block radiation rather than deliver energy. In February 2002 the Federal Trade Commission charged two sellers of metallic patches for phone earpieces that claimed to block up to 97 or 99 percent of radiation. The Good Housekeeping Institute, the magazine’s product testing laboratory, had tested such patches independently and found they did not reduce exposure from cell phones. The FTC said most of a phone’s emissions come from the antenna and other parts of the handset, not the earpiece, and that there was no scientific proof such shields significantly reduce exposure. The complaints, authorized by a 5-0 commission vote and filed in federal courts in Florida and California, also alleged that the companies falsely described their products as proven and tested.
The 5G era produced a sharper example. In May 2020 the British security firm Pen Test Partners took apart a USB device sold as 5G protection and found an ordinary 128-megabyte memory stick and a sticker, which the firm judged worth about £5. And Washington’s health department notes that some products in the category it tested for radioactivity also claim to protect people and pets from electromagnetic fields.
Reading the claims on a device
FDA’s own training material for device firms is explicit that registration and listing “does not, in any way, indicate FDA approval or clearance of establishments or products.” FDA treats any suggestion otherwise as misbranding. So a frequency product labeled as FDA registered tells you only that a firm filed paperwork.
A second document explains why so many of these products can be sold at all.
Under FDA’s general wellness policy, reissued in January 2026, the agency’s device center does not intend to examine low-risk products whose claims stop at things such as relaxation, stress management, sleep or fitness. The policy has two firm edges. A product that claims to treat or diagnose a specific disease falls outside it, and the guidance’s own examples include a claim to treat an anxiety disorder. A product built on a technology that carries risk without regulatory controls, such as lasers or radiation exposure, is not low risk either. A frequency device sold for relaxation and the same box sold for stage 4 cancer are, legally, very different products.
Five questions sort most products quickly:
- Which condition, and which regulation? Legitimate electromagnetic therapies name both. A vague promise of wellness names neither.
- Is a prescription required? The bone stimulators and post-surgical shortwave devices are prescription-only by regulation.
- What energy is delivered, and where? A frequency band aimed at a tissue is a dose. A claim of resonating with your cells is not.
- How many unrelated diseases does it claim? A device said to treat cancer, diabetes, stroke and depression at once matches the pattern in the FDA warning letter above.
- Was it tested against a sham? The bone stimulator trials compared real and inactive devices. A testimonial page is not a comparison.
No device on a nightstand replaces a medical assessment in the situations below. A fracture that is still painful or unstable months after injury needs an orthopedic evaluation; the regulated stimulators are prescription devices for exactly that situation. Depression that persists despite treatment needs professional care, and thoughts of self-harm need it immediately. Anyone in the US can call or text 988 to reach the national crisis line.
If you have a pacemaker, an insulin pump or another implanted device, NCCIH notes that some magnets can interfere with such devices, so any magnetic or electromagnetic product is worth raising with the clinician who manages it. If you own jewelry on one of the radioactive product lists, your state radiation control program can tell you the local disposal rule.
The Takeaway
The word frequency tells you nothing about whether a device works. What matters is what physical energy it delivers, to which tissue, for which named condition, and under which regulation. Bone stimulators, rTMS and post-surgical shortwave devices can answer all four questions, whatever debate remains about how well they work. Frequency generators, quantum pendants and phone shields have been answered instead by warning letters, prosecutions, teardowns and radiation tests.
Sources
- Food and Drug Administration, Federal Register (public inspection copy). “Physical Medicine Devices; Reclassification of Non-Invasive Bone Growth Stimulators. Final amendment; final order, Doc. 2026-07366, Docket FDA-2020-N-1053, scheduled for publication April 16, 2026 (new 21 CFR 890.5870).” public-inspection.federalregister.gov
- Food and Drug Administration. “FDA presentation to the Orthopaedic and Rehabilitation Devices Panel on non-invasive bone growth stimulators, September 8, 2020 (Class III, PMA; first PMA P790002 approved 11/06/1979).” fda.gov
- Cochrane Database of Systematic Reviews. “Griffin XL, Costa ML, Parsons N, Smith N. "Electromagnetic field stimulation for treating delayed union or non-union of long bone fractures in adults." Cochrane Database of Systematic Reviews, 2011. PubMed. DOI: 10.1002/14651858.CD008471.pub2.” pubmed.ncbi.nlm.nih.gov
- Bioelectromagnetics. “Peng L, Fu C, Xiong F, et al. "Effectiveness of Pulsed Electromagnetic Fields on Bone Healing: A Systematic Review and Meta-Analysis of Randomized Controlled Trials." Bioelectromagnetics, 2020. PubMed. DOI: 10.1002/bem.22271.” pubmed.ncbi.nlm.nih.gov
- Electronic Code of Federal Regulations. “21 CFR 882.5805, Repetitive transcranial magnetic stimulation system (Class II; 76 FR 44491, July 26, 2011).” ecfr.gov
- Food and Drug Administration, Federal Register (GovInfo). “Medical Devices; Neurological Devices; Classification of Repetitive Transcranial Magnetic Stimulation System. Final rule, FR Doc. 2011-18806, 76 FR 44489, July 26, 2011, effective August 25, 2011 (records FDA's class II order of October 7, 2008).” govinfo.gov
- Electronic Code of Federal Regulations. “21 CFR 890.5290, Shortwave diathermy, including (b) nonthermal shortwave therapy (Class II; 80 FR 61302, Oct. 13, 2015).” ecfr.gov
- National Center for Complementary and Integrative Health, National Institutes of Health. “Magnets for Pain: What You Need To Know (content last updated January 2023).” nccih.nih.gov
- Food and Drug Administration, Center for Devices and Radiological Health. “Warning Letter, CMS 639553, November 18, 2022, to a seller of bioresonance ultrasound and frequency devices.” fda.gov
- Courthouse News Service. “Report on the sentencing of a San Diego seller of unapproved micro-current frequency devices (February 9, 2010).” courthousenews.com
- NBC San Diego. “Report on the 51-month sentence of a seller of unapproved electronic devices (February 9, 2010).” nbcsandiego.com
- Times of San Diego (City News Service). “Report on an 18-month federal sentence for selling devices described as Rife machines (October 5, 2015).” timesofsandiego.com
- Sydney Morning Herald (author's archive). “Ben Hills, investigation of Rife-type frequency devices, Sydney Morning Herald, 30 December 2000, p. 25 (author's archive copy; headline not shown on the page).” benhills.com
- International Archives of Allergy and Immunology. “Schoni MH, Nikolaizik WH, Schoni-Affolter F. "Efficacy trial of bioresonance in children with atopic dermatitis." International Archives of Allergy and Immunology, 1997. PubMed. DOI: 10.1159/000237460.” pubmed.ncbi.nlm.nih.gov
- Forschende Komplementarmedizin. “Pihtili A, Galle M, Cuhadaroglu C, et al. "Evidence for the efficacy of a bioresonance method in smoking cessation: a pilot study." Forschende Komplementarmedizin, 2014. PubMed. DOI: 10.1159/000365742.” pubmed.ncbi.nlm.nih.gov
- Authority for Nuclear Safety and Radiation Protection (ANVS), Netherlands. “News item on quantum pendants, anti-5G pendants, negative ion jewellery and sleep masks that emit ionizing radiation, with advice to store them away safely (16 December 2021).” english.autoriteitnvs.nl
- The Lansing Journal (republishing an Illinois Emergency Management Agency release of May 15, 2018). “Republication of the IEMA release on quantum and scalar energy pendants and radiation exposure (May 17, 2018).” thelansingjournal.org
- Utah Department of Environmental Quality, Division of Waste Management and Radiation Control. “Negative Ion Technology, Consumer Products and Radiation (first published August 13, 2019; modified March 11, 2026).” deq.utah.gov
- Washington State Department of Health. “Radioactive Consumer Products (undated page).” doh.wa.gov
- Federal Trade Commission. “FTC Charges Sellers of Cell Phone Radiation Protection Patches with Making False Claims (February 20, 2002).” ftc.gov
- Pen Test Partners. “Phil Eveleigh, teardown of a USB device sold as 5G protection, security blog post (28 May 2020).” pentestpartners.com
- Food and Drug Administration, CDRH Learn. “Device Registration and Listing: An Introduction, Part 1 (training module, undated).” fda.gov
- Food and Drug Administration. “General Wellness: Policy for Low Risk Devices, final guidance (January 6, 2026; supersedes September 2019 version).” fda.gov