Glutathione Injection Side Effects, Sulfites and Asthma

Some injectable glutathione preparations contain sulfites — sodium metabisulfite or similar — as preservatives and antioxidants that keep the glutathione from degrading in the vial. Sulfites are the same preservatives found in wine, dried fruit and some medications, and for most people they are harmless.

For a minority, they are not. Sulfite sensitivity produces reactions ranging from flushing, hives and wheezing to, rarely, anaphylaxis, and it is markedly more common in people with asthma — particularly those whose asthma is severe or steroid-dependent. The FDA requires a sulfite warning on every injectable drug that contains one for exactly this reason. Separately, inhaled glutathione has provoked bronchospasm in people with asthma in small studies, through a mechanism that may involve the sulfur chemistry of the molecule itself rather than a preservative. Both lines of evidence point the same way: asthma is the history that matters.

What this means in practice: we ask about asthma and about any previous reaction to sulfites — including reactions to wine or dried fruit that involved wheezing or hives — before prescribing. A person with asthma is not automatically excluded, but the clinician will want to know how severe it is, whether it is well controlled, and whether a sulfite-free preparation is available and appropriate. Your clinician can tell you whether the specific product dispensed contains a sulfite; it is on the label and in the pharmacy's documentation, and asking is reasonable.

Injectable glutathione has a manufacturing history worth knowing about. In 2019 the FDA warned about a batch of glutathione powder distributed to compounding pharmacies that contained high levels of endotoxin — a bacterial by-product that causes fever, chills, nausea and low blood pressure when injected — after several patients became ill. Glutathione is not an FDA-approved drug, so every injectable preparation is compounded, and the quality of what is in the vial is the pharmacy's responsibility rather than a manufacturer's under FDA license.

That is not a reason to avoid it. It is a reason to use a state-licensed pharmacy that tests its products and to know where yours came from — which is the same rule as every compounded product on this site. Your clinician will tell you which pharmacy dispenses your prescription, that it is licensed in your state, and how to obtain the batch documentation for your lot.

A same-day message to your clinician for any of these, and a stop until you have spoken: wheezing, chest tightness or shortness of breath after an injection; hives or a rash spreading beyond the site of the injection; fever or chills within hours of an injection, which may indicate a contaminated product and must be reported; or a reaction at the site that is hot, spreading and increasingly painful over a day or more.

Swelling of the lips, face or throat, or difficulty breathing, is an emergency — call 911 first and tell us afterwards. If you have asthma and carry a rescue inhaler, keep it with you for the first few injections.

Asthma — how severe, how controlled, what you take for it. Any previous reaction to sulfites, or to any injection. Any history of anaphylaxis to anything. Pregnancy or breastfeeding, for which there is no safety data. And the full medication and supplement list, because although glutathione has no known interactions of consequence, the absence of evidence is not the same as evidence of absence, and we would rather know.