About

Oliver Grundmann, Ph.D., received a bachelor’s degree in pharmacy and European pharmacist license from the University of Münster, Germany, in 2004. He then pursued graduate studies at the University of Florida, where he completed a master’s degree in Forensic Toxicology in 2007 and a Ph.D. in Pharmaceutical Sciences in the same year. His research interests include the search for new treatment options from natural products for Central Nervous System and Gastrointestinal diseases such as anxiety, depressive disorders, irritable bowel syndrome, and gastrointestinal tract cancers. Since 2016, a major collaborative research focus has been on Kratom (Mitragyna speciosa), its pharmacology, therapeutic potential, and patterns of use. Dr. Grundmann also has an interest in the implementation and impact of national and international collaborations for curricular development in health sciences, with an emphasis on distance and online education. He serves as the Director and faculty advisor for the online Master of Science and graduate certificate programs in Pharmaceutical Chemistry and Clinical Toxicology at the College of Pharmacy. In September 2023, he assumed the role of assistant dean of lifelong learning at the UF College of Pharmacy.

Research topics

• Medicine
• Computer Science
• Psychology
• Political Science
• Geography
• Psychiatry
• Clinical psychology
• Traditional medicine
• Environmental health
• Internet privacy
• Chemistry
• World Wide Web
• Business

Selected publications

• Indole Alkaloids as Biased Opioid Receptor Modulators

  Pharmaceuticals · 2026-02-28

  articleOpen access1st authorCorresponding

  Background: Opioid receptors are a commonly used target for treatment of pain conditions. Most opioids used in therapy are linked to adverse effects such as tolerance, dependence, and respiratory depression. Indole alkaloids acting on opioid receptors may provide a novel molecular mechanism to confer analgesic effects. Results: Indole alkaloids such as ibogaine and mitragynine act on μ-opioid receptors as biased full or partial agonists that do not, or much less strongly, recruit β-arrestin compared to non-biased agonists. The recruitment of β-arrestin has been linked to adverse effects, most notably substantial respiratory depression. The molecular mechanism of biased activation has been proposed to be associated with accommodation of the indole structure that leads to a different spatial orientation of amino acid residues in transmembrane regions 2 and 3 of the μ-opioid receptor as well as extracellular helix 8. Conclusions: Naturally occurring indole alkaloids show biased G-protein coupled activation of opioid receptors with limited recruitment of β-arrestin, thus limiting commonly observed adverse effects. Indole alkaloids may present a feasible structure to develop new biased opioid modulators with an improved risk-to-benefit ratio.

  PublisherOA PDFDOI

• Indole Alkaloids as Biased Opioid Receptor Modulators

  Preprints.org · 2026-01-29

  preprintOpen access1st authorCorresponding

  Background: Opioid receptors are a commonly used target for treatment of pain conditions. Most opioids used in therapy are linked to adverse effects such as tolerance, dependence, and respiratory depression. Indole alkaloids acting on opioid receptors may provide a novel molecular mechanism to confer analgesic effects. Results: Indole alkaloids such as ibogaine and mitragynine act on μ-opioid receptors as biased full or partial agonists that do not recruit β-arrestin. Recruitment of β-arrestin has been linked to adverse effects, most notably substantial respiratory depression. The molecular mechanism of biased activation has been proposed to be associated with accommodation of the indole structure that leads to a different spatial orientation of amino acid residues in transmembrane regions 2 and 3 of the μ-opioid receptor as well as extracellular helix 8. Conclusions: Naturally occurring indole alkaloids show biased G-protein coupled activation of opioid receptors without recruitment of β-arrestin thus limiting commonly observed adverse effects. Indole alkaloids may present a feasible structure to develop new biased opioid modulators with an improved risk-to-benefit ratio.

  PublisherOA PDFDOI

• List of contributors

  Elsevier eBooks · 2025-09-27

  book-chapter
  PublisherDOI

• The Impact of Diverse Kratom Products on Use Patterns, Dependence, and Toxicity

  Current Psychiatry Reports · 2025-08-05 · 7 citations

  reviewSenior author
  PublisherDOI

• Honoring the Extensive and Impactful Contributions of Prof David J Greenblatt, MD: Founding Editor of <i>Clinical Pharmacology in Drug Development</i>

  Clinical Pharmacology in Drug Development · 2025-07-31

  editorialOpen accessSenior authorCorresponding

  “Do not follow where a path may lead. Go instead where there is no path and leave a trail.” -Ralph Waldo Emerson Clinical pharmacology is an interdisciplinary field that encompasses laboratory research, drug development, therapeutic optimization, and patient care. Among the giants in the field of clinical pharmacology stands Prof David Greenblatt, a visionary, pioneer, and highly influential scientist and mentor. Fueled by passion, dedication, and a tireless resolve to venture into uncharted territories, Dr Greenblatt's unparalleled contributions have significantly advanced the discipline of clinical pharmacology. A native of Newton, Massachusetts, Dr Greenblatt is a magna cum laude graduate of Amherst College (1966). He graduated from Harvard Medical School in 1970, then trained in internal medicine at the Montefiore Hospital, New York City (1970-1971), and on the Harvard Medical Service at Boston City Hospital (1971-1972). Following a fellowship in Clinical Pharmacology at Massachusetts General Hospital under the mentorship of Dr Jan Koch-Weser (1972-1974), he stayed on to head their Clinical Pharmacology Unit (1975-1979). Dr Greenblatt has been on the faculty of the Tufts University School of Medicine (TUSM) and the staff of Tufts Medical Center since 1979. He is a senior faculty member in the Graduate Program in Pharmacology and Drug Development and has previously served as chair of the Department of Pharmacology and Experimental Therapeutics at TUSM, program director and associate program director of the institution's Clinical/Translational Research Center, and chair of the Institutional Review Board. He has served as a postdoctoral training supervisor or dissertation supervisor for more than 60 trainees, most of whom have gone on to positions as university-based investigators or scientists in industry. In his inspiring, tireless, and accomplished career journey spanning more than 5 decades, Dr Greenblatt has significantly contributed essential knowledge to expand our understanding of drug interactions and pharmacokinetic principles, especially in the field of psychopharmacology and psychiatry. Dr Greenblatt has been recognized for his exemplary contributions to clinical pharmacology by major national and international scientific organizations. He received the McKeen Cattell Award from the American College of Clinical Pharmacology (ACCP) in 1985, the Distinguished Service Award in 2001, the Distinguished Investigator Award in 2002, and the Hartmut Derendorf Mentorship in Clinical Pharmacology Award in 2024. Dr Greenblatt joined ACCP in 1974 and is one of the longest-serving fellows in ACCP history. After joining the Board of Regents in 1981, he was elected as president-elect in 1994-1996 and served as president from 1996 to 1998. Having completed his terms on the Board and Executive Committee, he became an honorary regent and has actively engaged with ACCP in numerous ways. He has served on the Nominations and Publications Committees, on the Working Groups for Online Communities, Pearls for Practice, and Revenue Sources. Having authored approximately 800 manuscripts, over 175 reviews or book chapters, 100 editorials or commentaries, and a dozen books, Dr Greenblatt has contributed significantly to the field of clinical pharmacology. In 2013, when ACCP launched its new journal, Clinical Pharmacology in Drug Development (CPDD), Dr Greenblatt served as its founding editor and built the journal into an authoritative voice on high-quality clinical pharmacology studies in drug development. Published monthly and indexed in the PubMed/MEDLINE database, CPDD is a respected resource for critical information sought by the global clinical pharmacology community. “Having David as my mentor during these years contributed greatly to my subsequent professional career. Many of his former students found their way to industry and notably the clinical phase of drug development. And many of these, in turn, were invited back to discuss their experiences with the next generation of students.” “What I know Dr Greenblatt most for, however, is having been blessed with his amazing mentorship starting as a doctoral student in the Department of Pharmacology and Experimental Therapeutics at TUSM, in the early 1990s. I owe my career in clinical pharmacology, as do so many of my Greenblatt lab peers, to the solid foundation that was built under his guidance and mentorship. To me, Dr Greenblatt will always be a special person that I hold in the highest regard, and a standard to which other mentors should be compared. I could not be more thankful and blessed that he was, and continues to be, a key person in my professional journey.” “At a recent presentation that he gave, … I was reminded of all the fundamental lessons that he taught me and that are carried forward in my work on a weekly basis. I was also reminded of how seriously he takes his mentoring, support, and guidance of all of those in his lab, both past and present. When Dr Greenblatt's students complete formal training, his support and mentorship do not end.” In John C Maxwell's words, “A leader is one who sees more than others see, who sees farther than others see, and who sees before others do.” Long before the founding of the journal CPDD, Dr Greenblatt advocated for the publication of early-phase clinical studies that not only advance our understanding of drug action, pharmacokinetics, safety, and efficacy of new drugs but also contribute to the assessment of generic drugs. Such studies, which often follow well-established and relatively straightforward trial designs, are frequently overlooked even though they form the basis for dose selection for later-phase pivotal studies and ultimately assessing the benefit-to-risk profile of a drug. In the early 2000s, the pharmaceutical industry was suddenly faced with mandates on research transparency, which meant that early Phase 1 studies needed to be published, but the majority of contemporary journals in the field were not inclined to publish the findings of such studies despite their well-recognized importance. Seeing this need for the industry to publish their Phase 1 studies as an opportunity, Dr Greenblatt led the effort at ACCP to invest resources into the founding of CPDD, a peer-reviewed, PubMed-indexed journal that has been published since 2012 and is now in its 14th volume. John Quincy Adams once said, “If your actions inspire others to dream more, learn more, do more, and become more, you are a leader.” Throughout his tenure as editor-in-chief of CPDD, Dr Greenblatt has led, facilitated, and constantly inspired researchers from academia, industry, and regulatory agencies to submit articles of early-stage clinical trials resulting in CPDD becoming a go-to platform for publishing high-quality and well-designed trials that inform the global clinical pharmacology community about developing trends and evolving concepts that can optimize trial design, reduce costs, and advance critical knowledge about a drug candidate to inform later-stage trials. If the science of a manuscript was sound, Dr Greenblatt dedicated a considerable amount of time and effort to guide the authors and reviewers to ensure the results of such manuscripts would be published. With a keen eye, extensive knowledge, and vast experience, he worked diligently to make CPDD a welcoming home for high-quality science. Dr Greenblatt's tenure as founding editor-in-chief of CPDD resulted in a journal with a solid foundation, and ACCP is extremely thankful for his many decades of dedicated service to the organization, the CPDD journal, and the global clinical pharmacology community.

  PublisherOA PDFDOI

• De facto opioids: Characterization of novel 7-hydroxymitragynine and mitragynine pseudoindoxyl product marketing

  Drug and Alcohol Dependence · 2025-05-08 · 22 citations

  article
  PublisherDOI

• Prevalence and Use Patterns of Kava (Piper Methysticum) in a Us Nationally Representative Sample

  SSRN Electronic Journal · 2025-01-01

  preprintOpen accessSenior author
  PublisherDOI

• Kratom – neue Phytoarzneidroge mit polypharmakologischen Effekten

  Zeitschrift für Phytotherapie · 2025-09-01

  article1st authorCorresponding
  PublisherDOI

• Diversification of Kratom in US Markets: Results from an Online Survey and Chemical Assay of Products

  Substance Use & Misuse · 2025-08-25

  articleSenior authorCorresponding

  ) products in the US have diversified from dried leaf to now include edibles, extracts, teas, and tonics. Higher alkaloid content and/or greater oral exposure across formulations expose consumers to potentially greater amounts of alkaloids per serving in a shorter duration of time, thereby potentially increasing product effect and risk profiles. Six kratom vendors disseminated our anonymous online survey. Participants reported on products use patterns, perceived benefits, and adverse effects. Product samples were classified: powders, edibles, liquids, and teas and were analyzed for alkaloid content using UPLC-MS/MS. The final sample consisted of 421 participants, using 61 products. They were 61.8% male and 46.3% between 31 and 50 years. Whole-leaf powders were most popular and reported to provide more pain relief, energy, and improved sleep compared to other products. The most common adverse effect was constipation (73.4%). Edibles were associated with tolerance while liquids were associated with consuming more than intended. Alkaloid content was significantly higher in edibles and whole-leaf powders compared to teas and concentrated liquid extracts. Diversification of kratom products and higher alkaloid content per serving or dose expose consumers to inadvertent toxicity. Further clinical investigation of risk profiles for different formulations is needed.

  PublisherDOI

• Kratom use: a review of patterns and motivations

  Elsevier eBooks · 2025-09-27 · 1 citations

  book-chapterSenior author
  PublisherDOI

Frequent coauthors

• Kirsten E. Smith

  National Institute on Drug Abuse

  68 shared

• Katherine Hill

  CNS Research (United States)

  59 shared

• Corneliu N. Stanciu

  Dartmouth College

  51 shared

• Charles A. Veltri

  Midwestern University

  35 shared

• Saunjoo L. Yoon

  26 shared

• Jack E. Henningfield

  Pinney Associates (United States)

  24 shared

• Darshan Singh

  Universiti Sains Malaysia

  23 shared

• Veronika Butterweck

  Max Zeller Söhne (Switzerland)

  22 shared

Labs

• Department of Cellular and Systems PharmacologyPI

Education

• B.S., Pharmacy

  University of Münster

  2004

• M.S., Forensic Toxicology

  University of Florida

• Ph.D., Pharmaceutical Sciences

  University of Florida