Mark Robin Geier (1948 – March 20, 2025) was an American de-licensed physician and controversial professional witness who testified in more than 90 cases regarding allegations of injury or illness caused by vaccines. By 2013, Geier's medical license had been suspended or revoked in every state in which he was licensed over concerns about his

autism Autism, also known as autism spectrum disorder (ASD), is a neurodevelopmental disorder characterized by differences or difficulties in social communication and interaction, a preference for predictability and routine, sensory processing d ...

treatments and his misrepresentation of his credentials to the Maryland Board of Health, to which he falsely claimed to be a board-certified geneticist and

epidemiologist Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population, and application of this knowledge to prevent diseases. It is a cornerstone ...

. Geier and his son David Geier are frequently cited by proponents of the discredited claim that vaccines cause autism. Geier's credibility as an expert witness has been questioned in 10 court cases. In 2003, a judge ruled that Geier presented himself as an expert witness in "areas for which he has no training, expertise and experience". In other cases in which Geier has testified, judges have labeled his testimony "intellectually dishonest", "not reliable" and "wholly unqualified". Another judge wrote that Geier "may be clever, but he is not credible". Geier's scientific work has also been criticized; when the

Institute of Medicine The National Academy of Medicine (NAM), known as the Institute of Medicine (IoM) until 2015, is an American nonprofit, non-governmental organization. The National Academy of Medicine is a part of the National Academies of Sciences, Engineerin ...

reviewed vaccine safety in 2004, it dismissed Geier's work as seriously flawed, "uninterpretable", and marred by incorrect use of scientific terms. In 2003, the

American Academy of Pediatrics The American Academy of Pediatrics (AAP) is the largest professional association of pediatricians in the United States. It is headquartered in Itasca, Illinois, and maintains an office in Washington, D.C. The AAP has published hundreds of poli ...

criticized one of Geier's studies, which claimed a link between vaccines and autism, as containing "numerous conceptual and scientific flaws, omissions of fact, inaccuracies, and misstatements". In January 2007, a paper by the Geiers was retracted by the journal ''Autoimmunity Reviews''. ''

New Scientist ''New Scientist'' is a popular science magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organ ...

'' reported that the supposed

institutional review board An institutional review board (IRB), also known as an independent ethics committee (IEC), ethical review board (ERB), or research ethics board (REB), is a committee at an institution that applies research ethics by reviewing the methods proposed ...

(IRB) that Geier claimed approved his experiments with autistic children was located at Geier's business address and included Geier, his son David and wife, a business partner of Geier's, and a plaintiff's lawyer involved in vaccine litigation. The Maryland State Board of Physicians referred to it as a "sham IRB" that did not meet the requirements of state or federal law.

Career

Geier worked at the Laboratory of General and Comparative Biochemistry,

National Institutes of Health The National Institutes of Health (NIH) is the primary agency of the United States government responsible for biomedical and public health research. It was founded in 1887 and is part of the United States Department of Health and Human Service ...

in the 1970s and 1980s as a student researcher (1969–1970), research geneticist (1971–1973), staff fellow (1973–1974), on the professional staff (1974–1978), and as a guest worker (1980–1982). He then examined vaccine safety issues, with scientists, scientific institutions, and judges criticizing this body of work as "tainted by faulty methodology". At the time of his death he was a self-employed geneticist and along with his son David, he operated several organizations from his private address in Maryland, including the Institute for Chronic Illness and the Genetic Centers of America. As a professional witness he testified in more than 90 vaccine cases, in support of the view that there is a clear link between thiomersal and autism. His credibility as an expert witness was criticized during many proceedings before the Special Masters. In a 2010 decision, the presiding legal authority wrote, "In summary, I conclude that all of the Geier epidemiologic studies are not reliable, and cannot be accorded any weight."

Controversies

Mark and David Geier published several speculative articles about a possible link between

autism spectrum disorder Autism, also known as autism spectrum disorder (ASD), is a neurodevelopmental disorder characterized by differences or difficulties in social communication and interaction, a preference for predictability and routine, sensory processing di ...

s and vaccines that contain

thimerosal Thiomersal ( INN), or thimerosal ( USAN, JAN), also sold under the name merthiolate, is an organomercury compound. It is a well-established antiseptic and antifungal agent. The pharmaceutical corporation Eli Lilly and Company named it Merthi ...

, generating some controversy. The

dispute the conclusion of the Geiers' paper claiming a correlation between thimerosal and autism, and criticized it for "numerous conceptual and scientific flaws, omissions of fact, inaccuracies, and misstatements".

Limited access to Vaccine Safety Datalink records

The Geiers were granted access to the Vaccine Safety Datalink records, but the National Immunization Program found that "during the first visit the researchers conducted unapproved analysis on their datasets and on the second visit attempted to carry out unapproved analyses but did not complete this attempt. This analysis, had it been completed, could have increased the risk of a

confidentiality Confidentiality involves a set of rules or a promise sometimes executed through confidentiality agreements that limits the access to or places restrictions on the distribution of certain types of information. Legal confidentiality By law, la ...

breach. Before leaving, the researchers renamed files for removal which were not allowed to be removed. Had it gone undetected, this would have constituted a breach of the rules about confidentiality."

Lupron

The Geiers developed a protocol for treating autism that uses the drug

Lupron Leuprorelin, also known as leuprolide, is a manufactured version of a hormone used to treat prostate cancer, breast cancer, endometriosis, uterine fibroids, for early puberty, as part of transgender hormone therapy, or to perform chemical c ...

, which acts as

chemical castration Chemical castration is castration via anaphrodisiac drugs, whether to reduce libido and sexual activity, management of cancer, to treat cancer, or otherwise. Unlike orchiectomy, surgical castration, where the gonads are removed through an incision ...

. Mark Geier has called Lupron "the miracle drug" and the Geiers have marketed the protocol across the U.S. The Geiers filed three U.S.

patent application A patent application is a request pending at a patent office for the grant of a patent for an invention described in the patent specification and a set of one or more claim (patent), claims stated in a formal document, including necessary officia ...

s on the use of Lupron in combination with

chelation therapy Chelation therapy is a medical procedure that involves the administration of chelating agents to remove heavy metals from the body. Chelation therapy has a long history of use in clinical toxicology and remains in use for some very specific medic ...

as a treatment protocol for autism based on the hypothesis that "

testosterone Testosterone is the primary male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting se ...

mercury" along with low levels of

glutathione Glutathione (GSH, ) is an organic compound with the chemical formula . It is an antioxidant in plants, animals, fungi, and some bacteria and archaea. Glutathione is capable of preventing damage to important cellular components caused by sources ...

blocks the conversion of

DHEA Dehydroepiandrosterone (DHEA), also known as androstenolone, is an endogenous steroid hormone precursor. It is one of the most abundant circulating steroids in humans. DHEA is produced in the adrenal glands, the gonads, and the brain. It functio ...

to DHEA-S and therefore raises

androgens An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...

which in turn further lower glutathione levels, ultimately providing a connection between autism, mercury exposure, and

hyperandrogenism Hyperandrogenism is a medical condition characterized by high levels of androgens. It is more common in women than men. Symptoms of hyperandrogenism may include acne, seborrhea, hair loss on the scalp, increased body or facial hair, and infre ...

, specifically

precocious puberty In medicine, precocious puberty is puberty occurring at an unusually early age. In most cases, the process is normal in every aspect except the unusually early age and simply represents a variation of normal development. There is early developm ...

.Methods for screening, studying and treating disorders with a component of mercurial toxicity
" US

Patent application A patent application is a request pending at a patent office for the grant of a patent for an invention described in the patent specification and a set of one or more claim (patent), claims stated in a formal document, including necessary officia ...

20060058271, March 16, 2006Methods of treating disorders having a component of mercury toxicity
" US

20060058241, March 16, 2006 According to expert pediatric endocrinologists, the Lupron protocol for autism is supported only by

junk science Junk science is spurious or fraudulent scientific data, research, or analysis. The concept is often invoked in political and legal contexts where facts and scientific results have a great amount of weight in making a determination. It usually con ...

. The reaction of mercury and testosterone which the therapy is intended to treat is actually based on a protocol used to create testosterone crystals for use in

X-ray crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring th ...

rather than a physiological process that occurs in the human body. Although

Abbott Laboratories Abbott Laboratories is an American multinational medical devices and health care company with headquarters in Abbott Park, Illinois, in the United States. The company was founded by Chicago physician Wallace Calvin Abbott in 1888 to formulate k ...

sells Lupron in the U.S. and cooperated with the Geiers in one of the patent applications, it is no longer pursuing work with them, citing the nonexistence of scientific evidence to justify further research. When treating an autistic child, the Geiers order several dozen lab tests, costing $12,000: if at least one testosterone-related result is abnormal, the Geiers consider Lupron treatments, using 10 times the daily dose ordinarily used to treat precocious puberty. The therapy costs approximately $5,000 per month. The Geiers recommend starting treatment on children as young as possible, and say that some need treatment through adulthood.

Expert witness testimony

Geier has testified as an expert witness in Federal Court, and has been accepted as an expert witness in approximately 100 hearings for parents seeking compensation from the

National Vaccine Injury Compensation Program The Office of Special Masters of the U.S. Court of Federal Claims, popularly known as "vaccine court", administers a no-fault system for litigating vaccine injury claims. These claims against vaccine manufacturers cannot normally be filed in s ...

for alleged vaccine injuries to their children. In 10 of these cases, "Dr. Geier's opinion testimony has either been excluded or accorded little or no weight based upon a determination that he was testifying beyond his expertise."John and Jane Doe v. Ortho-Clinical Diagnostics, Inc
", US District Court for the Middle District of North Carolina, July 6, 2006

Medical licenses revoked

On April 27, 2011, the

Maryland Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...

State Board of Physicians suspended Geier's medical license as an "emergency action", saying he "endangers autistic children and exploits their parents by administering to the children a treatment protocol that has a known substantial risk of serious harm and which is neither consistent with

evidence-based medicine Evidence-based medicine (EBM) is "the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. It means integrating individual clinical expertise with the best available exte ...

nor generally accepted in the relevant scientific community". The board ruled that Geier misdiagnosed patients, diagnosed patients without sufficient tests, and recommended risky treatments without fully explaining the risks to the parents. They also ruled that he misrepresented his credentials, including during an interview with the board. Geier's lawyer, Joseph A. Schwartz III said the basis of the complaint was a "bona fide dispute over therapy", and hoped for a fair hearing to challenge the board's accusations. The suspension was reaffirmed in May 2011, and upheld on appeal in March 2012 after a full evidentiary hearing before the Office of Administrative Hearings in Maryland. Geier's licenses to practice medicine in the states of

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

Virginia Virginia, officially the Commonwealth of Virginia, is a U.S. state, state in the Southeastern United States, Southeastern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States between the East Coast of the United States ...

and

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

were suspended as well. In June 2012, Geier was charged with violation of the Maryland suspension by continuing to practice medicine without a license. In August 2012, Geier's license was formally revoked by the Maryland State Board of Physicians. On 5 November 2012, the

Missouri Missouri (''see #Etymology and pronunciation, pronunciation'') is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it border ...

Medical board and the

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

Department of Financial and Professional Regulation revoked Geier's license, both citing action taken by the Maryland State Board of Physicians. On April 12, 2013, Geier's last medical license in the United States was revoked by the state medical board of

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

. In 2011, his son David was charged by the Maryland State Board of Physicians with practicing as a licensed physician when he only has a

Bachelor of Arts A Bachelor of Arts (abbreviated B.A., BA, A.B. or AB; from the Latin ', ', or ') is the holder of a bachelor's degree awarded for an undergraduate program in the liberal arts, or, in some cases, other disciplines. A Bachelor of Arts deg ...

degree in biology, and was fined $10,000 in July 2012.

Lawsuit against Maryland Board of Physicians

On December 21, 2012, a lawsuit was filed against the Maryland State Board of Physicians by Anne Geier. The claim made in case 371761-V was that a cease and desist order filed by the Maryland State Board of Physicians against Mark Geier, for prescribing medicine to his family after his license was suspended, was posted publicly on the Board's website disclosing their private medical information. The decision of the board was upheld on appeal.

Personal life

Geier and his wife Anne played

doubles tennis Men's doubles, Women's doubles or Mixed doubles are sports having two players per side, including; * Beach volleyball * Doubles badminton * Doubles curling * Footvolley * Doubles pickleball * Doubles squash * Doubles table tennis * Doubles ...

. Their son David is also an avid tennis player. Anne died of metastatic melanoma at age 67 in 2014. Geier died on March 20, 2025 in Jupiter, Florida.

Notes and references

External links

Dr Mark Geier Severely Criticized
by Stephen Barrett, M.D.
IOM.edu
– Immunization Safety Review: Vaccines and Autism,

, May 17, 2004
Dr Mark Geier in error of magnitude
– Court report, June 25, 1990 {{DEFAULTSORT:Geier, Mark 1948 births 2025 deaths 20th-century American physicians American geneticists American anti-vaccination activists Autism researchers George Washington University School of Medicine & Health Sciences alumni Johns Hopkins University faculty Living people Physicians from Washington, D.C. Thiomersal and vaccines Uniformed Services University of the Health Sciences faculty Autism pseudoscience Date of birth missing (living people)