"However, another study — one of many that could be cited — Effect of N-acetyl-cysteine on the hypoxic ventilatory response and erythropoietin production: linkage between plasma thiol redox state and O2 chemosensitivity, found that very modest doses of NAC, 200 mg three times daily, massively increased erythropoeitin production and increased the hypoxic ventilatory response."