meningitidis , have been recently described, one of which involved bacteriemia (Mustapha et al., 2020)

N-Acetyl-L-Cysteine (NAC) by Designs for Health provides 900 mg per capsule of this powerful amino acid precursor to glutathione the body's master antioxidant.* It supports healthy liver function, optimal detoxification, antioxidant status, muscle recovery, lung health, and brain function.* N-Acetyl-L-Cysteine is formulated to support healthy liver function and normal detoxification by promoting glutathione production.* Glutathione is the body's primary antioxidant for neutralizing free radicals and clearing unwanted compounds.* Individual results may vary based on diet, lifestyle, and overall health status.* Key benefits include support for normal glutathione status, healthy liver function, optimal detoxification, antioxidant status, muscle function and recovery, and brain and lung health.* These benefits stem from NAC's role as the rate-limiting precursor to the body's glutathione production.* Take one capsule per day, or as directed by your healthcare practitioner

They are not illegal to buy or own, but they are not approved for human use, so are not subject to the quality controls that govern pharmaceutical manufacturing
That said, the classic formula consistently includes the following components
Diet, antibiotic use, stress, and infections can disrupt the microbial ecosystem
A two-week course of transcutaneous vagal nerve stimulation improves global sleep: Findings from a randomised trial in community-dwelling adults