Objective:

To present a case of copper deficiency myeloneuropathy resulting from chronic, unsupervised zinc supplementation undertaken for unproven COVID-19 prevention, and to highlight the neurologic consequences associated with misinformation-driven supplement use.

Background:

The COVID-19 pandemic was marked by dissemination of unverified health advice, prompting many individuals to adopt self-directed therapies such as zinc supplementation. While zinc is generally considered safe, excessive intake impairs gastrointestinal copper absorption leading to copper deficiency. Copper is required for myelin and neuronal integrity; deficiency can result in myeloneuropathy with painful sensory loss, weakness, and gait instability.

Design/Methods:

A 65-year-old woman with minimal change disease treated with prednisone and rituximab, pancytopenia, COPD, and chronic vitamin B12 and D deficiencies presented with progressive bilateral lower extremity pain, numbness, and weakness. She reported electric shock-like sensations and severe allodynia extending from the feet to the hands, resulting in gait impairment that necessitated the use of a walker. Gabapentin and tramadol provided minimal relief.

CT head and infectious workup was unremarkable. Electromyography and nerve conduction studies identified right carpal tunnel syndrome and a generalized sensorimotor peripheral neuropathy. Laboratory evaluation demonstrated elevated zinc (130 µg/dL) and markedly reduced serum copper (<10 µg/dL). Further history revealed daily over-the-counter zinc use since 2021, initiated after exposure to online claims regarding immune benefits for COVID-19 prevention. Copper supplementation was initiation with discontinuation of supplemental Zinc with no further progression but lack of improvement on initial follow up. 

Results:

NA

Conclusions:

This case demonstrates the neurologic harm that may result from misinformation and unsupervised supplement use. Unproven COVID-19 prevention practices can cause lasting, preventable neurologic deficits. In this case, given the 4-year history of daily zinc supplementation, there will likely be some residual deficits despite initiation of copper supplementation. Clinician vigilance and proactive counseling are necessary to mitigate the long-term consequences of misinformation-driven self-medication.