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Ten Years Later: Gadolinium Toxicity – A Disease of Degrees
Editorial by Sharon Williams
November 12, 2025
In early 2015, I opened a post with the following question: Why does a Gadolinium Toxicity diagnosis have to be full-blown NSF (Nephrogenic Systemic Fibrosis) or nothing at all? I went on to say that we believe Gadolinium Toxicity is a “disease of degrees”, which can manifest itself in many ways depending on how much gadolinium someone retains. And it can occur in patients with normal renal function.
Here we are ten years later, in 2025, and our belief about retained gadolinium causing a disease with varying degrees of severity is stronger than ever. That belief is based on the results of the Patient Survey that Hubbs Grimm and I conducted last year along with patient advocates Sarah Ratnam and Catriona Walsh. We recently released our first paper that focuses on the symptoms reported by 316 survey participants after MRIs with a gadolinium-based contrast agent (GBCA). The patients had normal and near normal renal function at the time of their MRIs. 185 of the participants have one or more test results that confirm they retained gadolinium for more than 30 days and for as long as 22 years after contrast administration, including 14 years in pelvic bone, and 13 years in sigmoid colon tissue.
The similarities between the symptom reporting patterns of the survey participants closely mirror those published about the clinical presentation of early-phase NSF as described by Marckmann & Skov (2009). Based on what Marckmann wrote about NSF, it seems that NSF itself had varying degrees of severity. Marckmann (2009 & 2011) wrote that there were significant individual differences in the clinical course of NSF, even in end-stage renal disease (ESRD) patients, which seems to indicate that retained gadolinium could trigger a range of symptoms, with a varied clinical outcome in all patient populations.
The variability of the symptoms shows that even in severely renally impaired patients, gadolinium-induced NSF did not cause the exact same set of symptoms or level of severity.
Is NSF itself the “disease of degrees”? Do all patients affected by gadolinium manifest NSF to varying extents, but without the “N” or nephrogenic component? The many similarities between the early clinical picture of NSF and the symptoms reported by participants in our Patient Survey suggest that they do.
Rather than a new or separate disease entity for patients with normal renal function, such as Gadolinium Deposition Disease (GDD) as described by Semelka & Ramalho (2023), our survey findings suggest that GDD and NSF may reflect different points along a continuum of gadolinium-induced toxicity. In other words, what we are observing may be one gadolinium-induced disease process manifesting with varying degrees of severity, which is how Marckmann described NSF in his Severity Grading in 2009.
Gadolinium has the Potential to Harm All Patients (more…)
Can Symptoms of Gadolinium Toxicity be explained?
On August 25, 2020, I wrote an open letter to the FDA, Radiologists and Researchers about the symptoms of gadolinium toxicity that have not, as yet, been recognized by the FDA or medical community as being caused by retained gadolinium (Gd). I believe part of the problem stems from the fact that histopathological examination has not found any evidence that deposited Gd caused “harm” in the brain. However, the lack of physical evidence and abnormal blood tests does not mean that harmful events have not taken place in patients’ bodies. What if gadolinium affected the function of cells, especially nerve cells, and triggered a cascade of adverse events, experienced by the person as decidedly abnormal and unpleasant sensations? Would that be easily detected on histological examination of tissue, or blood tests?
In my letter, I reviewed facts that we already know about Gd from the literature, in terms of both its retention after contrast administration and its effects at a cellular level. Given that Gd has been shown to induce mitochondrial toxicity, interfere with ion channels, create neuronal hyperexcitability, and affect inflammatory processes, could Gd be affecting not only the part of the brain that controls many processes, but also peripheral and autonomic nerve endings, as well as dorsal root ganglia, to produce the many and varied symptoms that patients are experiencing?
We know that retention of Gd has been demonstrated in humans, that unexplained symptoms are occurring, and the neuronal effects of Gd have been demonstrated experimentally. Could it just be that the connection has not yet been made, and when considered together, all these facts might explain how patients’ symptoms are being caused by retained Gd from gadolinium-based contrast agents (GBCAs)?
I believe many symptoms of gadolinium toxicity can be explained by Gd-induced small fiber neuropathy (SFN) and long-standing neuropathic pain. Interestingly, as you will see in my letter, many symptoms of SFN are the same as the clinical symptoms associated with nephrogenic systemic fibrosis (NSF), which makes sense to me since the cause is the same.
Symptoms of Gadolinium Toxicity: Can their cause be explained? is available for download as a PDF and it will be posted in Our Research in the Research section of our website. The reason for making my letter available to the public now is to inform doctors, researchers, and affected patients about gadolinium-related facts that do not seem to be widely recognized. My hope is that more research will be conducted that involves evaluation and testing of patients who have retained gadolinium and are experiencing SFN-like symptoms, which, until now, have been unexplained and perplexing to clinicians who are not familiar with the potential toxic effects of retained gadolinium.
Sharon Williams
Study Reports Gadolinium Clearance Times for 135 Contrast MRI Cases including Agent Administered for 63 Unconfounded Cases
On December 5, 2018, Hubbs Grimm and Sharon Williams, coauthors of GadoliniumToxicity.com, released their fifth research paper on gadolinium retention from Gadolinium-based Contrast Agents (GBCAs) administered for contrast-enhanced MRIs. The paper is titled Gadolinium Clearance Times for 135 Contrast MRI Cases and includes the contrast agents for the unconfounded cases.
Drawing on the contrast MRI history and 24-hour gadolinium urine testing results that have been received from members of the MRI-Gadolinium-Toxicity Support Group, the study reports retrospectively on 135 cases with 218 urine test results, including 63 unconfounded cases with 81 test results. The participants all had normal kidney function and report having symptoms of gadolinium toxicity. The results reported are dramatic and involve all linear and macrocyclic GBCAs currently in use in the United States.
About the Gadolinium Clearance Time Report
In addition to reporting on additional cases received since our previous paper in 2017, we now report the contrast agents received with each unconfounded case. Analysis of the these cases produced trend lines over time that indicate typical gadolinium found in 24-hour urine testing for each of the agents including Dotarem, Gadavist, Magnevist, MultiHance, Omniscan, OptiMARK, and ProHance. The graphs and tables provide helpful information for both patients and medical practitioners trying to understand their test results. The analysis of clearance times for each agent is presented on a separate page.
The results show that all agents, both linear and macrocyclic, do not clear from the body in a few days as most patients are told. None of the test results in the first 2.5 months following a contrast-enhanced MRI was within the reference range used by Mayo Clinic Laboratories. It should be noted that the contrast agent and test result information presented is from people who believe they are suffering symptoms of gadolinium toxicity since their contrast-enhanced MRI. It is not known whether the clearance times presented would also apply to individuals who are not symptomatic.
The complete set of test results, without any data that would identify patients, is available to other researchers upon request.
With the evidence provided that clearance times are much longer for all of the agents than expected by medical practitioners, the authors present five recommendations for needed actions by medical professionals, other researchers, government agencies, and contrast agent manufacturers.
Final Thoughts
We want to thank members of the MRI-Gadolinium-Toxicity Support Group for their willingness to share their test results and other information with us. Our papers would not be possible without their continued support.
We urge patients, clinicians, and researchers to read the entire report and share as appropriate with your families, caregivers, and colleagues.
Read the Gadolinium Clearance Times for 135 Contrast MRI Cases Report
Hubbs Grimm and Sharon Williams
Gadolinium Toxicity 