Amino acids
NAC — timing, dose & interactions
Cysteine donor that replenishes glutathione, the body's main intracellular antioxidant. Low oral bioavailability (~5–10%).
Also known as N-acetylcysteine
Timing
When to take it
Often taken on an empty stomach; take with food if it causes nausea.
Interactions
NAC with other supplements
No documented supplement interactions in our dataset.
Safety
Medications & health conditions
NAC can intensify nitroglycerin. NAC enhances nitrate-induced vasodilation, which has caused low blood pressure and severe headaches.
Antioxidants may interfere with cancer treatment. Some chemotherapy and radiation work partly through oxidative damage; high-dose antioxidants could reduce their effect. Discuss every supplement with your oncology team.
Buying guide
What to look for on the label
NAC
- Capsules in sealed blister packs or with desiccant (NAC oxidizes)
FAQ
Common questions
When is the best time to take NAC?
On waking. Often taken on an empty stomach; take with food if it causes nausea.
Should NAC be taken with food?
It can be taken with or without food. Often taken on an empty stomach; take with food if it causes nausea.
Sources