Glutathione (GSH) is a tripeptide thiol (γ-L-glutamyl-L-cysteinylglycine) that serves as the body's master antioxidant and primary intracellular redox regulator. In the Indian context, it is widely used as a prescription and over-the-counter supplement for its hepatoprotective, skin-lightening, and detoxification properties. Its clinical use is supported by its role in Phase II detoxification, free radical scavenging, and immune system modulation.
Adult: Oral: 500mg to 1000mg per day, in divided doses (e.g., 500mg once or twice daily). For therapeutic purposes (liver support), 500mg twice daily is common. For skin lightening (off-label), doses of 500-1000mg/day are used.
Note: Take on an empty stomach or as directed by the physician. Oral tablets/capsules should be swallowed whole with a glass of water. For better absorption, some practitioners recommend taking with Vitamin C. Avoid taking with high-protein meals simultaneously, as amino acids may compete for absorption.
Glutathione exerts its effects through multiple pathways: 1) Direct scavenging of reactive oxygen species (ROS) and reactive nitrogen species (RNS). 2) Serving as an essential cofactor for glutathione peroxidase (GPx), which reduces hydrogen peroxide and lipid hydroperoxides to water and alcohols. 3) Acting as a substrate for glutathione S-transferase (GST), which conjugates with electrophilic toxins, drugs, and carcinogens, facilitating their excretion via bile or urine. 4) Regenerating oxidized antioxidants like Vitamin C and E back to their active forms. 5) Modulating immune function by influencing lymphocyte proliferation and cytokine production. 6) In skin lightening, it inhibits tyrosinase activity by switching melanin synthesis from eumelanin (dark) to pheomelanin (light) and by quenching free radicals involved in pigment production.
Pregnancy: Category N (Not classified by US FDA). Insufficient human data. Animal studies are not suggestive of direct harm. Use only if clearly needed and potential benefit justifies potential risk to the fetus. Not recommended for cosmetic purposes during pregnancy.
Driving: No known effects on the ability to drive or operate machinery.
| Acetaminophen (Paracetamol) | Glutathione is used as an antidote in overdose by replenishing depleted stores and conjugating the toxic NAPQI metabolite. Therapeutic doses may offer some protection against hepatotoxicity. | Moderate |
| Chemotherapeutic agents (e.g., Cisplatin, Doxorubicin) | May reduce the therapeutic efficacy of certain chemotherapies by detoxifying them or reducing oxidative stress intended to kill cancer cells. Conversely, it may protect against nephrotoxicity (cisplatin). CONSULT ONCOLOGIST. | Major |
| Immunosuppressants | Theoretical potential to modulate immune response. Clinical significance unknown. | Moderate |
| Antioxidants (High-dose Vitamin C, Vitamin E) | Synergistic antioxidant effect. Vitamin C helps recycle oxidized glutathione (GSSG) back to reduced form (GSH). | Minor |
Same composition (Glutathione (500mg)), different brands: