N-Acetyl-L-Cysteine (NAC) is a derivative form of the amino acid cysteine, which is better absorbed by the body. It is often used as a dietary supplement for its role as a precursor to glutathione.

Adults may consume up to 1200 mg NAC per day without adverse effects. There are supplements on the market that recommend a higher dosage. Therefore, the RIVM advises users to ensure that you do not take too much. This supplement contains 1000 mg NAC per daily dose of 2 capsules.

Quercetin is a bioflavonoid found in various plant foods such as apples and onions.

Zinc bound to glycinate (zinc bisglycinate) is a so-called chelated form, in which zinc is linked to the amino acid glycine. This form is known for its good absorption and mildness for the stomach.