Glutathione is the body's most important antioxidant — and oral supplements barely absorb. Here is what an IM glutathione injection involves, who benefits, and how to book at Lambert Medical in Surbiton.
Glutathione — sometimes called the "master antioxidant" — is a naturally occurring molecule found in every cell in your body. It is involved in nearly every major biological process: antioxidant defence, immune regulation, liver detoxification, and cellular energy production. When levels are optimal, the body functions well. When they fall — through ageing, illness, chronic stress, environmental toxins or poor nutrition — the consequences are felt across multiple systems.
At Lambert Medical Practice in Surbiton, glutathione intramuscular (IM) injections are one of the most popular treatments among patients seeking to support cellular health, improve skin clarity, and reduce the burden of oxidative stress on the body. This guide explains what glutathione is, why injection is more effective than oral supplementation, and what a session at our clinic involves.
Glutathione (gamma-L-glutamyl-L-cysteinyl-glycine, or GSH) is a tripeptide — a small protein made from three amino acids: glutamine, cysteine and glycine. It is synthesised inside cells, particularly in the liver, which maintains the highest concentration in the body. Unlike vitamins that must be obtained from diet, glutathione is endogenously produced — your cells make it themselves.
Its main roles in the body include:
Glutathione directly neutralises free radicals and reactive oxygen species (ROS). It also regenerates vitamins C and E after they have been oxidised, extending their antioxidant effect. It is the primary intracellular antioxidant — the last line of defence inside cells.
Glutathione is essential for the proliferation and function of lymphocytes (white blood cells). It supports the balanced regulation of inflammation and plays a role in the innate immune response to viral and bacterial infection.
The liver uses glutathione in Phase II detoxification — conjugating it with toxins, heavy metals and drug metabolites to form water-soluble compounds that can be excreted via bile and urine. Low glutathione impairs detoxification capacity.
Glutathione inhibits tyrosinase, the enzyme responsible for melanin production. By reducing melanin synthesis and switching production from darker eumelanin to lighter phaeomelanin, glutathione is associated with improvements in skin tone evenness and reduction of hyperpigmentation.
Glutathione is widely available as an oral supplement, but there is a fundamental problem with taking it by mouth: the digestive system breaks it down before it reaches the bloodstream.
Glutathione is a peptide — it is cleaved by enzymes in the gut, particularly in the small intestine, into its component amino acids. These amino acids are absorbed and can be used by cells to synthesise new glutathione, but this is a slower and less efficient process than direct delivery. Studies measuring plasma glutathione levels after oral supplementation consistently show modest absorption — estimated at 10–20% under best conditions, and sometimes less.
Liposomal glutathione (encapsulated in fat vesicles to protect it from gut enzymes) improves oral absorption, but still falls significantly short of injectable bioavailability.
Intramuscular (IM) injection bypasses the gut entirely. Glutathione injected into muscle tissue is absorbed directly into the bloodstream through the capillary bed in muscle, achieving plasma concentrations that cannot be replicated by any oral preparation.
At Lambert Medical Practice, glutathione IM injections are administered by Dr Alexis Nelson or our trained nursing team. Here is what to expect:
Patients most likely to benefit from glutathione IM injections include:
Glutathione injection is not a treatment for any specific medical condition, and Lambert Medical does not recommend or promote it for therapeutic purposes beyond antioxidant and wellness support. If you have specific health concerns, a full GP consultation is the appropriate starting point.
Lambert Medical Practice offers both intramuscular (IM) and intravenous (IV) glutathione. The key difference is speed and peak plasma concentration:
Your clinician will advise on the most appropriate route based on your goals and preferences at consultation.
IM and IV glutathione available at Lambert Medical Practice. Same-week appointments in Surbiton — no GP referral needed.
Also at Lambert Medical: IV therapy Surbiton · IV drips guide