NOW Supplements, NAC (N-Acetyl Cysteine) 600 mg with Selenium, 250 Veg Capsules

Clinical trials typically use 600-1,800 mg daily. NOW Foods NAC 600mg delivers 600mg NAC per capsule, which we classify as Therapeutic relative to that range.

See the "Also consider" section below for two alternatives. Choose based on form preference (Capsule vs alternatives), dose adequacy, and third-party testing.

Yes — GMP Certified, Third-Party Tested. Third-party testing verifies ingredient identity and label accuracy.

Yes — Amazon Subscribe & Save is available for this product. Enrolling locks in a recurring delivery at a reduced per-unit price.

Yes, NAC at 600mg daily is the standard clinical dose and is considered safe for most adults. NOW Foods products are GMP certified and third-party tested for purity and potency.

NAC may have mild blood pressure-lowering effects and could potentially interact with antihypertensive medications. Consult your healthcare provider before combining NAC with blood pressure medications.

Common side effects include mild nausea, digestive upset, or a sulfurous taste or smell. These are typically mild and can be minimized by taking NAC with food. The sulfur odor is normal for NAC supplements.

NAC is actually the clinical antidote for acetaminophen overdose and supports glutathione production, which helps the liver process acetaminophen. However, do not use NAC as a reason to exceed recommended acetaminophen doses. Consult your doctor.

NAC is generally not associated with kidney stone formation. In fact, some research suggests NAC may have protective effects against kidney damage. However, individuals with a history of cystine stones should consult their doctor.

The recommended dose is 1 capsule (600mg) taken 1-2 times daily. For general antioxidant support, 600mg once daily is sufficient. For respiratory or liver support, 600mg twice daily (1200mg total) is commonly used.