Updated on April 10, 2023
Glutathione, a tripeptide naturally produced in the liver from three amino acids, is the body’s most essential antioxidant, and its ability to neutralize free radicals in cells and aid in detoxification processes has highlighted it as a promising therapeutic for a wide range of health conditions, including many challenging neurological conditions.* When a practitioner and a patient consider trying a new therapeutic option like glutathione, one of the first things that comes to mind is the question of potential side effects. Regardless of the purported health benefits of a therapeutic option, it might not be worth using if its side effects outweigh its benefits. In the case of glutathione IV therapy side effects, some patients worry that direct injection into the bloodstream could have an off-target impact.
So far, there is no data to indicate this is the case. However, there are lifestyle-related impacts to glutathione IV therapy that makes it less preferable for some patient populations who can benefit most from the compound, which makes it less convenient than alternatives like oral supplementation. Therefore, as supplement delivery technology continues to advance, it makes sense to consider using oral glutathione supplements alongside IV therapy.
No significant side effects of glutathione IV therapy have been reported in the available literature. Researchers first began exploring the intravenous administration of glutathione in the 1990s, and no indications of potentially adverse outcomes were observed. The only serious concern was that glutathione has a relatively short half-life in the bloodstream, which could potentially limit the duration of its efficacy.
These early results regarding glutathione safety and tolerability are supported by more recent clinical studies. For example, in a 2009 pilot evaluation of intravenous glutathione therapy for individuals with Parkinson’s disease at the University of South Florida, researchers reported that glutathione IV therapy that mildly benefited motor symptoms was “well tolerated” and posed “no safety concerns.” A 2017 case report yielded similar results. Although some researchers point out that the overall body of literature on safety is lacking, available studies indicate that with glutathione IV therapy, side effects are unlikely.
Nevertheless, when deciding whether or not to integrate glutathione IV therapy into a nutritional support strategy for a condition like Parkinson’s disease, it is important to recognize other ways that intravenous administration can impact a person’s life. Consider the fact that, in the studies that suggest IV glutathione can be a valuable therapeutic for patients with Parkinson’s disease, it has been administered at least once and sometimes twice a day. On top of the mobility challenges already facing individuals with Parkinson’s disease, the obligation to receive daily glutathione intravenously can make it even more difficult to maintain an independent lifestyle. This makes oral supplementation of glutathione an appealing option.
Similarly, although early studies suggest that glutathione administration can have benefits for autistic individuals,* IV therapy might not be the optimal solution when it comes to the recipient’s lifestyle concerns. For example, one of the most common autism symptoms is a high level of sensory sensitivity, which can make the process of intravenous administration a major challenge, especially for children. Because of the potential drawback of IV administration in these situations, clinicians and parents might want to consider oral glutathione supplement instead.
One of the primary reasons researchers began exploring glutathione IV therapy rather than oral supplementation was concern over the absorption of glutathione from the gastrointestinal (GI) tract. With early versions of supplements, glutathione was not entering the bloodstream sufficiently and being transported to the cells that needed it, such as those in the brain. However, in recent years, that obstacle has been resolved by the development of advanced delivery systems for glutathione. Thus, today’s supplement formulas can reach brain cells, and other cells outside the GI tract, so IV glutathione might not be necessary. Moreover, these new delivery systems address the issue related to glutathione’s short half-life, giving today’s advanced supplement formulas the potential to offer longer-lasting benefits for patients.
Although future studies will likely provide more conclusive data on the side effects of glutathione–whether administered intravenously or orally–today’s clinicians, patients, and parents can be relatively confident that supplemental glutathione is unlikely to lead to adverse effects. And for patient populations for whom daily IV administration is a significant lifestyle disruption, oral supplementation can be a valuable addition to an individual’s daily supplement regimen.
Tesseract Medical Research assesses and synthesizes the most relevant research on topics that researcher, clinicians, and patients care about most, including cutting-edge therapeutics like glutathione.
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